Count Back Within 20

20 - 8 = _____

• 11

• 12

• 18

• 19

12 - 7 = _____

• 5

• 7

• 12

• 19

Joe wants to subtract 5 from 15 on a number line. What should he do to perform this operation?

• Count back 5 steps from 15.

• Count back 5 steps from 10.

• Count back 15 steps from 5.

There are 19 frogs in the pond. 4 hopped away. How many are there now?

• 15

• 14

• 10

• 23

Subtract by counting back. 18-4=

• 14

• 13

• 12

20-8

• 11

• 12

• 13

• 14

Subtract by counting back. 16-3=

• 15

• 14

• 13

Subtract by counting back.

18 - 4 =

• 14

• 13

• 12

7 - 3 = ...............

• 3

• 6

• 2

• 4

Count back to subtract. Use a number line to help you.

6 – 4=........

• 5

• 3

• 2

• 4