Checking of Assignment

Drill: Give the greatest common factors of each of the following:

–16–32

»28»42

• 55• 99

• 36• 48

Sing the song…

• What is the song all about?• Do you have friends? Who

are they?• What are the things you do

together?

Problem Opener:

• Linda wants to buy her friends different kinds of candies. One type of candies is sold in packages of 6 pieces, other of 4 pieces and the third type in packages of 3 pieces. If Linda wants to buy the same amount for each type of candy, what is the smallest number of packages of candy that she can buy?

Using Listing the Multiples and Prime Factorization

•What is multiple? •How do we get the least common multiple of a set of numbers?

Multiple

• A multiple of a number is the product of that number and any other whole number.– 6 = 6, 12, 18, 24, 30, 36, 42, 48, 54, 60…– 12 = 12, 24, 36, 48, 60, 72, 84, 96, 108, 120…

LCM = 12

Find the LCM by listing the multiples:

• 21 and 15• 12 and 10• 16 and 20• 4 and 9• 15 and 35• 8, 12 and 20

Determine the LCM of the following:

a. 10 and 25

b. 20 and 50

c. 42 and 48

d. 20 and 45

e. 24 and 18

Write the GCF and LCM of each set of numbers use prime factorization.

1. 15 and 30 GCF= ____ LCM=____

2. 21 and 45 GCF= ____ LCM=____

3. 16 and 24 GCF= ____ LCM=____

4. 12 and 32 GCF= ____ LCM=____

5. 8 and 12 GCF= ____ LCM=____