Adding Integers with Counters

• White counters represent positive numbers.• Red or shaded counters represent negative numbers.• Lay or draw counters out to represent all of the numbers in the

problem.• Pair up negative and positive counters

– When you pair up negative and positive counters, they are equal to zero.

– These pairs are known as zero pairs.• Move any zero pairs that you have made off to the side.• Count up what you have left and that is your answer.

How to use counters

-9 + 49 negative counters+4 positive counters

Get rid of pairs. What do you have left?

5 negative counters

Answer = -5

6 + -86 positive counters +8 negative counters

Get rid of pairs. What do you have left?

2 negative counters

Answer = -2

-2 + 162 negative counters+16 positive counters

Get rid of pairs. What do you have left?

14 positive counters

Answer = 14

10 + -1010 positive counters+10 negative counters

Get rid of pairs. What do you have left?

0 units

Answer = 0

-5 + -55 negative counters+ 5 negative counters

Get rid of pairs. What do you have left?

10 negative counters

Answer = -10

Try these problems using counters!

1. -7 + -5 =

2. -2 + 6 =

3. 8 + -5 =

4. -10 + 3 =

5. -13 + 6 =

6. -8 + 8 =

7. -13 + -4 =

8. -9 + 8 =

9. 10 + -15 =

10. 3 + -3 =

-12

-7

3

4

-7

0

-17

-1

-5

0