the official sat online course39

Upload: jordy13

Post on 13-Apr-2018

231 views

Category:

Documents


0 download

TRANSCRIPT

  • 7/27/2019 The Official SAT Online Course39

    1/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLocat

    Help Profi le My Organizer My Bookm ar ks Logout

    to college successconnect

    Home Getting Started Lessons Practice Quizzes T ests Reports

    1

    Explanation for Correct Answer C :

    Choice (C) is correct. Converting from feet to inches, the length of

    the rope is inches. Therefore, the maximum number of

    pieces, each inches long, that can cut from the rope is

    Explanation for Incorrect Answer A :

    Choice (A) is incorrect. Converting from feet to inches, the length of

    the rope is inches. A total of pieces (not ), each

    inches long, can be cut from the -inch-long rope.

    Explanationfor IncorrectAnswer B :

    Choice (B) is incorrect. Converting from feet to inches, the length of

    the rope is inches. A total of pieces (not ), each

    inches long, can be cut from the -inch-long rope.

    Explanation for Incorrect Answer D :

    Choice (D) is incorrect. Converting from feet to inches, the length of

    the rope is inches. To cut a total of pieces, each

    inches long, would require inches of rope.

    Explanation for Incorrect Answer E :

    View Answers and Explanations

    Back to Score Report

    Online - Practice Test #3

    A r ope is feet long . Wha t is th e m ax im um nu m ber of pieces, each inch es

    long, that can be cut from the rope? ( foot inches)

    (A)

    (B)

    (C)

    (D)

    (E)

    ANSWERS ANDEXPLANATIONS

    Test Sections

    Section 1

    Section 3

    Section 4

    Section 5

    Section 6

    Section 7

    Section 8

    Section 9

    Sect ion 1 0

    https://satonlinecourse.collegeboard.org/SR/quizzesaction.dohttps://satonlinecourse.collegeboard.org/SR/examsaction.dohttps://satonlinecourse.collegeboard.org/SR/professionalreportshomeaction.dohttps://satonlinecourse.collegeboard.org/SR/helpAction.dohttps://satonlinecourse.collegeboard.org/SR/studentProfileAction.dohttps://satonlinecourse.collegeboard.org/SR/viewMyOrganizer.dohttp://popup%28%27/SR/mybookmarkaction.do'%20,600%20,600)https://satonlinecourse.collegeboard.org/SR/showExamAnswerExplanation.do?assessmentResultId=10846464&assessmentLocator=3CF8A603-66B4-9F5F-0099-8B08F172FC7B-1::AS&section=3CFB40E9-66B4-9F5F-9BE4-B7C62645AE24-1::S&fromPage=examscorereport&resultId=https://satonlinecourse.collegeboard.org/SR/showExamAnswerExplanation.do?assessmentResultId=10846464&assessmentLocator=3CF8A603-66B4-9F5F-0099-8B08F172FC7B-1::AS&section=3CFB40E9-66B4-9F5F-9BE4-B7C646DE3384-1::S&fromPage=examscorereport&resultId=https://satonlinecourse.collegeboard.org/SR/showExamAnswerExplanation.do?assessmentResultId=10846464&assessmentLocator=3CF8A603-66B4-9F5F-0099-8B08F172FC7B-1::AS&section=3CFB40D9-66B4-9F5F-9BE4-B7C6C098A518-1::S&fromPage=examscorereport&resultId=https://satonlinecourse.collegeboard.org/SR/showExamAnswerExplanation.do?assessmentResultId=10846464&assessmentLocator=3CF8A603-66B4-9F5F-0099-8B08F172FC7B-1::AS&section=3CFB40D9-66B4-9F5F-9BE4-B7C6008F7F8E-1::S&fromPage=examscorereport&resultId=https://satonlinecourse.collegeboard.org/SR/showExamAnswerExplanation.do?assessmentResultId=10846464&assessmentLocator=3CF8A603-66B4-9F5F-0099-8B08F172FC7B-1::AS&section=3CFB40D9-66B4-9F5F-9BE4-B7C651E87543-1::S&fromPage=examscorereport&resultId=https://satonlinecourse.collegeboard.org/SR/showExamAnswerExplanation.do?assessmentResultId=10846464&assessmentLocator=3CF8A603-66B4-9F5F-0099-8B08F172FC7B-1::AS&section=3CFB40D9-66B4-9F5F-9BE4-B7C6A4FC1CB5-1::S&fromPage=examscorereport&resultId=https://satonlinecourse.collegeboard.org/SR/showExamAnswerExplanation.do?assessmentResultId=10846464&assessmentLocator=3CF8A603-66B4-9F5F-0099-8B08F172FC7B-1::AS&section=3CFB40D9-66B4-9F5F-9BE4-B7C66FD69DDB-1::S&fromPage=examscorereport&resultId=https://satonlinecourse.collegeboard.org/SR/showExamAnswerExplanation.do?assessmentResultId=10846464&assessmentLocator=3CF8A603-66B4-9F5F-0099-8B08F172FC7B-1::AS&section=3CFB40D9-66B4-9F5F-9BE4-B7C62C0C2B44-1::S&fromPage=examscorereport&resultId=https://satonlinecourse.collegeboard.org/SR/showExamAnswerExplanation.do?assessmentResultId=10846464&assessmentLocator=3CF8A603-66B4-9F5F-0099-8B08F172FC7B-1::AS&section=3CFB40D9-66B4-9F5F-9BE4-B7C68A022024-1::S&fromPage=examscorereport&resultId=https://satonlinecourse.collegeboard.org/SR/fptscorereportaction.do?whereFrom=scoreNow&assessmentResultId=10846464https://satonlinecourse.collegeboard.org/SR/professionalreportshomeaction.dohttps://satonlinecourse.collegeboard.org/SR/examsaction.dohttps://satonlinecourse.collegeboard.org/SR/quizzesaction.dohttps://satonlinecourse.collegeboard.org/SR/lessonsaction.dohttps://satonlinecourse.collegeboard.org/SR/gettingstartedaction.dohttps://satonlinecourse.collegeboard.org/SR/studenthomeaction.dohttps://satonlinecourse.collegeboard.org/SR/logoff.dohttp://popup%28%27/SR/mybookmarkaction.do'%20,600%20,600)https://satonlinecourse.collegeboard.org/SR/viewMyOrganizer.dohttps://satonlinecourse.collegeboard.org/SR/studentProfileAction.dohttps://satonlinecourse.collegeboard.org/SR/helpAction.do
  • 7/27/2019 The Official SAT Online Course39

    2/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLocat 2

    Choice (E) is incorrect. Converting from feet to inches, the length of

    the rope is inches. To cut a total of pieces, each

    inches long, would require inches of rope.

    2

    Explanation for Correct Answer C :

    Choice (C) is correct. When two lines intersect, vertical angles areformed. Since vertical angles have equal measures and since is a

    line, then Since we have

    which simplifies to so

    Explanation for Incorrect Answer A :

    Choice (A) is not correct. If were then we would have

    Solving this equation for gives

    However, not Therefore, cannot be

    Explanation for Incorrect Answer B :

    Choice (B) is not correct. If were then we would have

    Solving this equation for gives

    However, not Therefore, cannot be

    Explanation for Incorrect Answer D :

    Choice (D) is not correct. If were then we would have

    Solving this equation for gives

    However, not Therefore, cannot be

    Lines and intersect at a point as shown above. If wha t is the v alue

    of

    (A)

    (B)

    (C)

    (D)

    (E)

    ANSWERS ANDEXPLANATIONS

  • 7/27/2019 The Official SAT Online Course39

    3/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLocat 3

    Explanation for Incorrect Answer E :

    Choice (E) is not correct. If were then we would have

    Solving this equation for gives

    However, not Therefore, cannot be

    3

    Explanation for Correct Answer D :

    Choice (D) is correct. If is the average of the three numbers

    and then From this it follows that

    Solving this equation for gives

    and

    Explanation for Incorrect Answer A :

    Choice (A) is not correct. It is given that is the average of the three

    numbers and Therefore, if were equal to then

    would be equal to However, is equal to not

    It follows that cannot be equal to

    Explanation for Incorrect Answer B :

    Choice (B) is not correct. It is given that is the average of the three

    numbers and Therefore, if were equal to then

    would be equal to However, is equal to

    not It follows that cannot be equal to

    Explanation for Incorrect Answer C :

    Choice (C) is not correct. It is given that is the average of the three

    numbers and Therefore, if were equal to then

    would be equal to However, is equal to

    The av erage (arit hm etic mean ) of the num bers shown above is What is the

    v alue of

    (A)

    (B)

    (C)

    (D)

    (E)

    ANSWERS ANDEXPLANATIONS

  • 7/27/2019 The Official SAT Online Course39

    4/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLocat 4

    Explanation for Incorrect Answer E :

    Choice (E) is not correct. It is given that is the average of the three

    numbers and Therefore, if were equal to then

    would be equal to However, is equal to not

    It follows that cannot be equal to

    4

    Explanation for Correct Answer C :

    Choice (C) is correct. The familys average daily use of electricity for

    a month was less than kilowatt-hours if and only if the point

    representing that month on the line graph lies below the horizontal

    grid line at There are three such points: July, August, and May.

    Explanation for Incorrect Answer A :

    Choice (A) is not correct. T he familys average daily use of electricity

    for a month was less than kilowatt-hours if and only if the point

    representing that month on the line graph lies below the horizontal

    grid line at There are three such points, not one.

    The line graph above shows the av erage daily use of electricit y , in kilowat t-hours,

    by a fa mily for ea ch m onth of a y ear, sta rt ing i n J uly . For how man y m onths of

    the y ear was the familys av erage daily use of electricity less than kilowatt-

    hours?

    (A) One

    (B) Two

    (C) Three

    (D) Fiv e

    (E) Eight

    ANSWERS ANDEXPLANATIONS

  • 7/27/2019 The Official SAT Online Course39

    5/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLocat 5

    Explanation for Incorrect Answer B :

    Choice (B) is not correct. T he familys average daily use of electricity

    for a month was less than kilowatt-hours if and only if the point

    representing that month on the line graph lies below the horizontal

    grid line at The two leftmost points on the graph lie below the

    horizontal grid line at but the point for May is a third such point.

    Explanation for Incorrect Answer D :

    Choice (D) is not correct. There are five months for which the

    familys average daily use of electricity was between and

    kilowatt-hours, but this is not what the question asked.

    Explanation for Incorrect Answer E :

    Choice (E) is not correct. There are eight months for which the

    familys average daily use of electricity was less than kilowatt-

    hours, but in only three of these months was the familys average

    daily use less than kilowatt-hours.

    5

    Explanation for Correct Answer A :

    Choice (A) is correct. The equation means that is equal

    to the sum of and which is equivalent to the statement is

    more than

    Explanation for Incorrect Answer B :

    Choice (B) is not correct. The equation represents thestatement is times as great as

    Explanation for Incorrect Answer C :

    Choice (C) is not correct. The equation represents the

    statement the sum of and is equal to

    Explanation for Incorrect Answer D :

    Choice (D) is not correct. The inequality represents the

    statement the sum of and is greater than

    Which of the following r epr esents t he sta tem ent, is m ore than ?

    (A)

    (B)

    (C)

    (D)

    (E)

    ANSWERS ANDEXPLANATIONS

  • 7/27/2019 The Official SAT Online Course39

    6/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLocat 6

    Explanation for Incorrect Answer E :

    Choice (E) is not correct. The inequality represents the

    statement the sum of and is greater than

    6

    Explanation for Correct Answer D :

    Choice (D) is correct. At Middletown High School, of juniors

    are members of the marching band. This means that of the

    juniors are members of the band. The fraction of the number of

    seniors who are members of the band is equal to the fraction of the

    number of juniors who are members of the band. Therefore, since

    there are seniors, the number of seniors in the band is

    Explanation for Incorrect Answer A :

    Choice (A) is not correct. If there were seniors in the band, then

    the fraction of the number of seniors who are members of the band

    would be The fraction of the number of seniors who are

    members of the band is equal to the fraction of the number of juniors

    who are members of the band, so of the juniors would be

    members of the band. However, the fraction of the number of juniors

    who are members of the band is not

    Explanation for Incorrect Answer B :

    Choice (B) is not correct. If there were seniors in the band, then

    the fraction of the number of seniors who are members of the band

    would be The fraction of the number of seniors who are

    members of the band is e ual to the fraction of the number of uniors

    At Middletown Hig h Sch ool, of ju ni ors are mem ber s of the m ar ch ing

    band. T he fraction of the nu m ber of seniors who are m em ber s of the ba nd is equ alto the fraction of the n um ber of juniors who are m embers of the band. How m any

    of the seniors are in the band?

    (A)

    (B)

    (C)

    (D)

    (E)

    ANSWERS ANDEXPLANATIONS

  • 7/27/2019 The Official SAT Online Course39

    7/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLocat 7

    who are members of the band, so of the juniors would be members

    of the band. However, the fraction of the number of juniors who are

    members of the band is not

    Explanation for Incorrect Answer C :

    Choice (C) is not correct. If there were seniors in the band, then

    the fraction of the number of seniors who are members of the band

    would be The fraction of the number of seniors who are

    members of the band is equal to the fraction of the number of juniors

    who are members of the band, so of the juniors would be

    members of the band. However, the fraction of the number of juniors

    who are members of the band is not

    Explanation for Incorrect Answer E :

    Choice (E) is not correct. If there were seniors in the band, then

    the fraction of the number of seniors who are members of the band

    would be The fraction of the number of seniors who are

    members of the band is equal to the fraction of the number of juniors

    who are members of the band, so of the juniors would be members

    of the band. However, the fraction of the number of juniors who are

    members of the band is not

    7

    Line intersects at point so tha t as shown above. If and

    (not shown) are the midpoints of and respectiv ely , which of the

    following mu st be true?

    I. an d ar e on th e sam e side of

    II. an d ar e on th e same side of

    III. an d ar e on opposite sides of

    (A ) I on ly

    (B) II on l

  • 7/27/2019 The Official SAT Online Course39

    8/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLocat 8

    Explanation for Correct Answer E :

    Choice (E) is correct. Consider each one of the statementsindependently to determine whether it must be true.

    Statement I concerns points and Point is the midpoint of

    so both and are to the left of point on It follows

    that and are on the same side of so statement I must be true.

    Statement II concerns points and Point is the midpoint of

    and so must lie to the right of on It follows

    that and are on the same side of so statement II must be

    true.

    Statement III concerns points and We know that is to the

    left of point on Point is the midpoint of so must lie

    to the right of on It follows that and are on opposite

    sides of so statement III must be true.

    Therefore, all three of the statements I, II, and III must be true.

    Explanation for Incorrect Answer A :

    Choice (A) is not correct. Statement I must be true, but statements II

    and III must also be true.

    Explanation for Incorrect Answer B :

    Choice (B) is not correct. Statement II must be true, but statements I

    and III must also be true.

    Explanation for Incorrect Answer C :

    Choice (C) is not correct. Statement III must be true, but statements

    I and II must also be true.

    Explanation for Incorrect Answer D :

    Choice (D) is not correct. Statements I and III must be true, but

    statement II must also be true.

    8

    (C) III only

    (D) I and III only

    (E) I, II, and III

    ANSWERS ANDEXPLANATIONS

    Georg e collected tokens worth a total of point s. If each of th e tokens has a

    v alue of either point s or point s, h ow m an y -point tokens did George

    collect?

  • 7/27/2019 The Official SAT Online Course39

    9/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLocat 9

    Explanation for Correct Answer E :

    Choice (E) is correct. Let be the number of -point tokens

    George collected, and let be the number of -point tokens he

    collected. Since George collected a total of tokens, it follows that

    Since these tokens are worth a total of points, it

    follows that Multiplying the first equation by

    ( ) and subtracting from the second gives

    and so Therefore, George collected tokens of value

    points.

    Explanation for Incorrect Answer A :

    Choice (A) is not correct. George collected tokens of value

    points, but the question asked for the number of -point tokens he

    collected.

    Explanation for Incorrect Answer B :

    Choice (B) is not correct. If George had collected only tokens of

    value points, he would then have tokens of value points.

    Then the total value of Georges tokens would be only

    points, not points.

    Explanation for Incorrect Answer C :

    Choice (C) is not correct. If George had collected only tokens of

    value points, he would then have tokens of value points.

    Then the total value of Georges tokens would be only

    points, not points.

    Explanation for Incorrect Answer D :

    Choice (D) is not correct. If George had collected only tokens of

    value points, he would then have tokens of value points.Then the total value of Georges tokens would be only

    points, not points.

    9

    (B)

    (C)

    (D)

    (E)

    ANSWERS ANDEXPLANATIONS

  • 7/27/2019 The Official SAT Online Course39

    10/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLoc 10

    Explanation for Correct Answer B :

    Choice (B) is correct. The equation is equivalent to

    From the table, only when

    Explanation for Incorrect Answer A :

    Choice (A) is incorrect. From the table,

    not

    Explanation for Incorrect Answer C :

    Choice (C) is incorrect. From the table, not

    Explanation for Incorrect Answer D :

    Choice (D) is incorrect. From the table, not

    Explanation for Incorrect Answer E :

    Choice (E) is incorrect. From the table, not

    10

    The function is defined by the table above. For wha t v alue of does

    (A)

    (B)

    (C)

    (D)

    (E)

    ANSWERS ANDEXPLANATIONS

    The figure a bov e shows a tr apezoid divided into three tria ngles. What is the area of

    the shaded trian gle?

    (A)

    (B)

    (C)

    (D)

  • 7/27/2019 The Official SAT Online Course39

    11/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLoc 1

    Explanation for Correct Answer D :

    Choice (D) is correct. We can find the area of the shaded triangle by

    subtracting the sum of areas of two unshaded triangles from the area

    of the trapezoid. The area of a trapezoid can be calculated by

    multiplying the average of the lengths of the bases by the altitude ofthe trapezoid. The length of bases of the trapezoid are and and

    so their average is The altitude of the trapezoid is so

    the area of trapezoid is The two unshaded triangles are

    congruent right triangles with legs of length and so the area of

    each unshaded triangle is The sum of the areas of the

    two unshaded triangles is then It follows that the area

    of the unshaded triangle is

    Explanation for Incorrect Answer A :

    Choice (A) is not correct. If the area of the shaded triangle was

    then the sum of the areas of the three triangles would be

    The sum of the areas of the three triangles is

    equal to the area of the trapezoid. However, the area of the trapezoid

    is not Therefore, the area of the shaded triangle cannot be

    Explanation for Incorrect Answer B :

    Choice (B) is not correct. If the area of the shaded triangle was

    then the sum of the areas of the three triangles would beThe sum of the areas of the three triangles is

    equal to the area of the trapezoid. However, the area of the trapezoid

    is not Therefore, the area of the shaded triangle cannot be

    Explanation for Incorrect Answer C :

    Choice (C) is not correct. The sum of areas of two unshaded triangles

    is However, the question is asking for the area of

    shaded triangle, not the sum of the areas of the unshaded triangles.

    Explanation for Incorrect Answer E :

    Choice (E) is not correct. If the area of the shaded triangle was

    then the sum of the areas of the three triangles would be

    The sum of the areas of the three triangles is

    equal to the area of the trapezoid. However, the area of the trapezoid

    is not Therefore, the area of the shaded triangle cannot be

    (E)

    ANSWERS ANDEXPLANATIONS

  • 7/27/2019 The Official SAT Online Course39

    12/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLoc 12

    11

    Explanation for Correct Answer E :

    Choice (E) is correct. In the -plane, the graph of

    is a parabola that intersects the -axis at

    and at When so

    the graph of is above the -axis for values less

    than below the -axis for values between and and

    above the -axis for values greater than It follows that all the

    values of for which are those values between

    and Of these, the smallest integer value is

    Explanation for Incorrect Answer A :

    Choice (A) is not correct. If then

    Therefore, is not a value of

    for which

    Explanation for Incorrect Answer B :

    Choice (B) is not correct. If then

    Therefore, is not a value of

    for which

    Explanation for Incorrect Answer C :

    Choice (C) is not correct. If then

    Therefore, is not a value of

    for which

    Explanation for Incorrect Answer D :

    Choice (D) is not correct. If then

    Therefore, is not a value of for

    which

    12

    What is the smal lest possible int eger v alue of for w hich

    (A)

    (B)

    (C)

    (D)

    (E)

    ANSWERS ANDEXPLANATIONS

    In the -plane, thr ee of the v ertices of a square are and If

    the square is reflected about the line which of the following is one v ertex of

  • 7/27/2019 The Official SAT Online Course39

    13/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLoc 13

    Explanation for Correct Answer A :

    Choice (A) is correct. Since three vertices of the square are

    and the fourth vertex is To find the reflection of

    across one can recall that the reflection of any point

    about is given by Therefore, the reflection

    of about the line is the point

    Alternatively, since has slope any line perpendicular to

    must have slope (the negative reciprocal of ). The line

    with slope that passes through is Thus the

    perpendicular from to intersects at

    Following this perpendicular an equal distance beyond shows

    that the reflection of about the line is

    Explanation for Incorrect Answer B :

    Choice (B) is not correct. The point lies on the line

    Thus is the reflection of itself, about the line

    The point is not one of the vertices of the original square and,

    thus, not a vertex of the resulting square.

    Explanation for Incorrect Answer C :

    Choice (C) is not correct. The point is the reflection of

    about the line The point is not one of the vertices of

    the original square, and so is not a vertex of the resulting

    square.

    Explanation for Incorrect Answer D :

    Choice (D) is not correct. The point lies on the line

    Thus is the reflection of itself, about the line

    The point is not one of the vertices of the original

    square and, thus, not a vertex of the resulting square.

    Explanation for Incorrect Answer E :

    Choice (E) is not correct. The point is the reflection of

    about the line The point is not one of the vertices of

    the resulting square?

    (A)

    (B)

    (C)

    (D)

    (E)

    ANSWERS ANDEXPLANATIONS

  • 7/27/2019 The Official SAT Online Course39

    14/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLoc 14

    the original square, and so is not a vertex of the resulting

    square.

    13

    Explanation for Correct Answer B :

    Choice (B) is correct. Since of the campers could swim, then

    there were swimmers among the campers and who couldnt

    swim; and since of the campers took climbing lessons, there were

    campers who took climbing lessons.

    Each of the campers who took climbing lessons either could swim

    or couldnt swim. Since a total of campers at the summer camp

    couldnt swim, at most of the campers who took climbing

    lessons couldnt swim. Therefore, the least possible number ofcampers taking climbing lessons who could swim is

    Explanation for Incorrect Answer A :

    Choice (A) is not correct. If were the least possible number of

    campers taking climbing lessons who could swim, then there could be

    campers who couldnt swim and also took climbing lessons. But

    there are only campers at the summer camp who couldnt swim.

    Explanation for Incorrect Answer C :

    Choice (C) is not correct. There were campers who took climbing

    lessons, but it need not be true that all of these campers could swim.

    Explanation for Incorrect Answer D :

    Choice (D) is incorrect. Since only campers took climbing

    lessons, there cannot be campers who took climbing lessons and

    also could swim.

    Explanation for Incorrect Answer E :

    Of the cam pers at a summ er cam p, could swim. If of the cam pers took

    climbing lessons, wha t w as the least possible num ber of cam pers taking clim bing

    lessons who could swim ?

    (A)

    (B)

    (C)

    (D)

    (E)

    ANSWERS ANDEXPLANATIONS

  • 7/27/2019 The Official SAT Online Course39

    15/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLoc 15

    Choice (E) is incorrect. There were swimmers among the

    campers, but the question asks for the least possible number of

    campers taking climbing lessons who could swim. Since only

    campers took climbing lessons, there cannot be campers who

    took climbing lessons and also could swim.

    14

    Explanation for Correct Answer E :

    Choice (E) is correct. Let be the point on for which

    Then triangle and triangle are both righttriangles. Since the measure of is and the hypotenuse of

    triangle has length the length of the side opposite is

    of so By the Pythagorean Theorem, it follows that

    The measure of is so

    triangle is an isosceles right triangle. We have so

    is also The length of segment is then

    Explanation for Incorrect Answer A :

    Choice (A) is not correct. Let be the point on for which

    We have and If the length

    of was then the length of would be

    However, the length of must be less than because is one

    leg of a right triangle with hypotenuse Therefore, the length of

    cannot be

    Explanation for Incorrect Answer B :

    Choice (B) is not correct. Let be the point on for which

    In above, the measur e of is and the measure of is

    What is the len gt h of seg ment

    (A)

    (B)

    (C)

    (D)

    (E)

    ANSWERS ANDEXPLANATIONS

  • 7/27/2019 The Official SAT Online Course39

    16/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLoc 16

    We have Also

    so

    Therefore, the length of cannot be

    Explanation for Incorrect Answer C :

    Choice (C) is not correct. Let be the point on for which

    We have and so

    Therefore, the length of cannot be

    Explanation for Incorrect Answer D :

    Choice (D) is not correct. Let be the point on for which

    The length of is but the length of is

    15

    Explanation for Correct Answer A :

    Choice (A) is correct. Taking the power of each side of

    gives This simplifies to

    Explanation for Incorrect Answer B :

    Choice (B) is not correct. equals not

    Explanation for Incorrect Answer C :

    Choice (C) is not correct. equals not

    Explanation for Incorrect Answer D :

    If an d wh at does equal in term s of

    (A)

    (B)

    (C)

    (D)

    (E)

    ANSWERS ANDEXPLANATIONS

  • 7/27/2019 The Official SAT Online Course39

    17/18

    1/23/2014 The Official SAT Online Course

    https://satonlinecourse.collegeboard.org /SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10846464&assessmentLoc 17

    Choice (D) is not correct. equals not

    Explanation for Incorrect Answer E :

    Choice (E) is not correct. equals not

    16

    Explanation for Correct Answer A :

    Choice (A) is correct. In each equation, is expressed in terms of

    two other variables; in all, a total in three variables appear in the

    right-hand sides of the three equations: and However, each

    variable appears in exactly two of the equations, once with acoefficient of and once with a coefficient of Hence if all three

    equations are added, all the variables on the right will cancel:

    It follows that and so the value of is

    Explanation for Incorrect Answer B :

    Choice (B) is not correct. Adding the three given equations yields

    which simplifies to

    not Therefore, the value of is not

    Explanation for Incorrect Answer C :

    Choice (C) is not correct. Adding the three given equations yields

    Based on th e system of equations abov e, wh at is th e v alue of

    (A)

    (B)

    (C)

    (D)

    (E)

    ANSWERS ANDEXPLANATIONS

  • 7/27/2019 The Official SAT Online Course39

    18/18

    1/23/2014 The Official SAT Online Course

    which simplifies to

    not Therefore, the value of is not

    Explanation for Incorrect Answer D :

    Choice (D) is not correct. Adding the three given equations yields

    that the value of is but the value of is

    Explanation for Incorrect Answer E :Choice (E) is not correct. Adding the three given equations yields

    which simplifies to

    Therefore, the value of is not

    Prev ious Section Next Section

    Back to Score Report

    Copyright 201 4The College Board.All rights reserved. Privacy Policy Terms of Use Contact Us

    http://popup%28%27http//www.collegeboard.org/satonlinecourse/contact_us.html')http://www.collegeboard.org/site-terms/http://www.collegeboard.org/privacy-policy/http://www.collegeboard.org/https://satonlinecourse.collegeboard.org/SR/fptscorereportaction.do?whereFrom=scoreNow&assessmentResultId=10846464https://satonlinecourse.collegeboard.org/SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10951175&assessmentLocator=3CF8A603-66B4-9F5F-0099-8B08F172FC7B-1::AS&section=3CFB40E9-66B4-9F5F-9BE4-B7C62645AE24-1::S&resultId=10951175https://satonlinecourse.collegeboard.org/SR/showExamAnswerExplanation.do?fromPage=examscorereport&assessmentResultId=10951175&assessmentLocator=3CF8A603-66B4-9F5F-0099-8B08F172FC7B-1::AS&section=3CFB40D9-66B4-9F5F-9BE4-B7C6C098A518-1::S&resultId=10951175