How can I multiply a How can I multiply a fraction by a whole fraction by a whole

number?number?

Team B: Tyderah Bradley, Troy Team B: Tyderah Bradley, Troy Erby, Cassandra Farzalo, Frank Erby, Cassandra Farzalo, Frank

Giannamore, Kari Harbaugh, Holly Giannamore, Kari Harbaugh, Holly HartshorneHartshorne

Let’s start with a review of Let’s start with a review of multiplying fractions:multiplying fractions:

To multiply a fraction To multiply a fraction by a fraction:by a fraction:

1.1. Multiply Multiply numerator by numerator by numeratornumerator

2.2. Multiply Multiply denominator by denominator by denominatordenominator

3.3. Simplify if Simplify if possiblepossible

Example:Example:

1

2

2

3

1 2

2 3

2

6

1

3x

x

x

Now you try to multiply a Now you try to multiply a fraction by a fraction:fraction by a fraction:

Write your answers Write your answers to these 3 to these 3 problems on your problems on your white board:white board:3

4

1

21

5

2

52

7

3

5

x

x

x

Let’s check your answers:Let’s check your answers:

3

4

1

2

3 1

4 2

3

81

5

2

5

1 2

5 5

2

252

7

3

5

2 3

5 7

6

35

xx

x

xx

x

xx

x

Now, let’s review how to change Now, let’s review how to change a whole number to a fraction:a whole number to a fraction:

Any number Any number divided by 1 equals divided by 1 equals that number.that number.

See: 5 1=5See: 5 1=5 So, you can put any So, you can put any

whole number over whole number over 1 without changing 1 without changing it’s value.it’s value.

See: See:

7 17

1

So, how can I use what I know to So, how can I use what I know to multiply a fraction times a whole multiply a fraction times a whole

number?number?

The problem:The problem:

57

10x

Steps to multiplying a whole Steps to multiplying a whole number by a fraction:number by a fraction:

1.Change the whole number to a 1.Change the whole number to a fractionfraction

2.Multiply numerator by numerator 2.Multiply numerator by numerator and denominator by denominatorand denominator by denominator

3. Simplify if possible3. Simplify if possible

57

10

5

1

7

10x x

5 7

1 10

35

10

x

x

35

10

7

2 ???

Hmmm…. But how can I simplify Hmmm…. But how can I simplify an improper fraction???an improper fraction???

Just remember TI- BO!Just remember TI- BO!No, not that kind!No, not that kind!TI-BO means top in- bottomTI-BO means top in- bottom

out. So:out. So:

7

22 7 3

1

2

Let’s review the steps we just Let’s review the steps we just learned:learned:

1.1. Put whole number Put whole number over 1over 1

2.2. Multiply Multiply numerators and numerators and denominatorsdenominators

3.3. Simplify if Simplify if possiblepossible

4.4. If my answer is If my answer is still improper, do still improper, do TI-BO!TI-BO!

Now you try it on your Now you try it on your whiteboard:whiteboard:

21

3

35

6

x

x

Check your answers and your Check your answers and your work:work:

21

3

2

1

1

3

2 1

1 3

2

3

35

6

3

1

5

6

3 5

1 6

15

6

5

2

2 5 21

2

x xx

x

x xx

x

So, how did you do?So, how did you do?

Give me a thumbs Give me a thumbs up if you got both up if you got both problems right!problems right!

Show me a thumbs Show me a thumbs to the side if you to the side if you got one problem got one problem right!right!

Point your thumb Point your thumb down to the ground down to the ground if you still need if you still need some help.some help.