Bagging Snacks: Choose Common Multiples or Common

Factors

Focus Question: How can you decide when finding common factors is useful in solving a problem? How can you find the GCF of two numbers?

Do Now

Use the terms factor, divisor, multiple, product, and divisible by to write as many statements as you can about the number sentence

7 x 9 = 63

Seven students are going on a trip. Sarah is in charge of buying snacks for the trip. Each person wants two health bars and a juice drink. How many should she buy of each?

Let’s Put Our Thinking Caps On

BAGGING SNACKS - PAGE 331) What are the possible numbers of snack

packs she can make so that the treats are shared equally? Describe each possibility.

24 apples36 bags of trail mix

Would we find the GCF or LCM to help us solve this problem?

24 – 24, 28, 72, 96

36 – 36, 72

LCM = 72

Would we find the GCF or LCM to help us solve this problem?

24 – 1, 2, 3, 4, 6, 8, 12, 24

36 – 1, 2, 3, 4, 6, 9, 12, 18, 36

Common Factors = 1, 2, 3, 4, 6, and 12

24 A36 T

12 A18 T

12 A18 T

8 A12 T

8 A12 T

8 A12 T

6 A9 T

6 A9 T

6 A9 T

6 A9 T

4 A6 T

5 A6 T

4 A6 T

4 A6 T

4 A6 T

4 A6 T

2 A3 T

2 A3 T

2 A3 T

2 A3 T

2 A3 T

2 A3 T

2 A3 T

2 A3 T

2 A3 T

2 A3 T

2 A3 T

2 A3 T

2) What is the greatest number of snack packs Jane can make? Explain.

3) Suppose Jane’s pet canary ruins six of the bags of trail mix. Jane wants to share the apples and the remaining bags of trail mix equally. What is the greatest number of snack packs Jane can make?

4) Suppose Jane’s mother replaces the six bags of trail mix. She also provides the group with 18 cans of juice. Each snack pack has the same number of apples, bags of trail mix, and cans of juice. What is the greatest number of snack packs Jane can make? Explain.

5) The cast of a play had a party. The drama teacher served 20 cookies & 40 carrot sticks as refreshments. Each cast member ate the same number of whole cookies and the same number of whole carrot sticks. Nothing was left over. The drama teacher did not eat. How many cast members might have been at the party? Explain.

CLASSWORKWorking in assigned groups, students will use chart paper to complete their given task.

HOMEWORKJournal Entry #2

a) Describe how you can find the common factors and the greatest common factor of two numbers.

b) What information does the greatest common factor of two numbers provide in a problem.