Document created by Jian Kang. All rights reserved.

Document created by Jian Kang. All rights reserved.

Grade 8 Gauss Math Competition Categorized: Geometry This document consists of a collection of problems that appeared in the Grade 8 Gauss Contests from 2001 to 2010. All the problems are original one found from CEMC’s website, where the solutions to these problems, along with other information, are provided. This document is created by Jian Kang (MathEasy123.wordpress.com), who collected these contest problems and put them into categories solely for study and teaching purposes. The standard of categorization employed is by no means the only way there is, as problems are often comprehensive. One is encouraged to come up with his or her own version of categorization.

Geometry Categorized here are geometry questions. These questions usually weigh more than one quarter of the total possible 150 marks in each of the past contests.

Contest Problems

Angle Problems These questions test one’s knowledge of angles. It’s crucial to know the fact that the sum of all three angles in a triangle is 180 degrees. Other knowledge such as the relationship of the angles created by parallel lines and intersecting lines is also very important. 2008, Q3

2009, Q4

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2003, Q5

Q2004, Q5

2005, Q7

2006, Q9

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2010, Q10

2007, Q12

2008, Q13

2003, Q13

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2005, Q13

2002, Q14

2001, Q16

2010, Q21

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2001, Q21

2004, Q23

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Length and Perimeter Problems This subcategory of questions requires the test participant to find the length of a line segment or a curve (the latter is very rare in this level of competition), or the perimeter of a certain shape. There are also problems that emphasizes on the relationship between area and perimeter, where several formulas must be memorized. These questions may also be categorized here. 2008, Q2

2010, Q5

2004, Q6

2002, Q10

2009, Q11

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2007, Q16

2006, Q16

2003, Q17

2006, Q18

2001, Q18

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2010, Q20

2005, Q20

2004, Q20

2002, Q21

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2009, Q23

2006, Q23

2005, Q23

2001, Q24

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2009, Q24

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Area Problems This subcategory consists of problems that require one to find the area of a certain shape. These questions are usually the more challenging ones in the contest. Careful inspection is often critical here. 2001, Q6

2005, Q11

2003, Q12

2006, Q12

2001, Q14

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2009, Q15

2010, Q16

2003, Q19

2009, Q19

2008, Q20

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2007, Q21

2005, Q21

2007, Q22

2002, Q22

2002, Q23

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2008, Q23

2010, Q24

2003, Q24

2007, Q25

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3D Objects, Volume and Surface Area Categorized here are questions involving 3D objects and requiring one to find the surface area and/or volumes. 2005, Q3

2007, Q5

2002, Q7

2006, Q7

2009, Q8

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2008, Q11

2003, Q15

2001, Q15

2004, Q15

2008, Q21

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2004, Q25