Subtracting by Counting Back

12 - 4 = . . .

• 8

• 9

• 10

15 - 6 = . . .

• 8

• 9

• 10

20 - 9 = . . .

• 10

• 11

• 12

When subtracting tens, what is the easiest way to count back?

• By counting forward from the smaller number

• By counting backward from the larger number

• By counting forward by ones

• By counting backward by ones

Subtract by counting back. 18-4=

• 14

• 13

• 12

Subtract by counting back. 18 - 4 =

• 14

• 13

• 12

19-8=

• 10

• 11

• 12

• 13

Subtract 7-3 by counting backward:

• 4

• 3

• 2

20-8

• 11

• 12

• 13

• 14

Subtract by counting back. 16-3=

• 15

• 14

• 13