Factors and Multiples

…and when to use them

Factors

• A factor is a number that divides another number evenly

• Factors pair up to make a product

• They are also called divisors

Factors of 20

• Numbers that divide 20 evenly are

• 1 and 20

• 2 and 10

• 4 and 5

• When these factors are paired together they make a product of 20

Multiples

• Multiples are the product of a whole number and another whole number

• They are used when skip counting

Multiples of 20

• 20 x 1 = 20

• 20 x 2 = 40

• 20 x 3 = 60

• 20 x 4 = 80

• 20 x 5 = 100

• Skip count by 20 to write multiples of 20

When to use factors

• Use factors when you want to show all the ways to divide a number evenly

• Sarah has 30 pieces of gum. She wants to divide the gum into equal groups. What size groups can she make?

• 1 group of 30 or 30 groups of 1• 2 groups of 15 or 15 groups of 2• 3 groups of 10 or 10 groups of 3• 5 groups of 6 or 6 groups of 5

When to use Multiples

• You can use multiples when an event is happening in cycles.

• A vending machine is filled every 7 days. If it was filled today, how many more times will it be filled in the next month?

• The machine is filled using a cycle of 7 days.

Multiples of 7

• It will be filled on the 7th day

• It will be filled on the 14th day

• It will be filled on the 21st day

• It will be filled on the 28th day

• It will be filled on the 35th day

• Could I keep going?

• Do I need to?

Your Turn

• Reggie has 40 erasers. He wants to put them into equal groups.

• What should he do to find all the groups he can make?

• Make a list of all the groups he can make.

• What is your list called?

Try another one

• The roller coaster at six flags goes down a hill every 8 seconds. How many times will it go down a hill in one minute?

• What should you do to list all the times the ride will go down a hill?

• When should you stop?

• What is your list called?

Work time…solve each problem and tell what you did to solve

• Brandon has 84 pieces of gum. He wants to put the gum into equal groups. What size groups can he make?

• McDonald’s can serve a customer every 12 seconds. How many customers can they serve in 2 minutes?

• Jada has 60 stickers. She wants to put the same number of stickers on a page. What are the ways she can do this?

• The phone at the doctor’s office rings every 15 seconds. How many times will it ring in 3 minutes?