Red & Black
Chips

Manipulatives and More

Red and black chips are often used to model addition and
subtraction of integers. A red chip represents -1 and a black
chip represents +1.** **

**Addition**

Addition is modeled by combining collections of chips. A red chip and a black chip "cancel" each other, so that any collection of chips with an equal number of reds and blacks represents the number 0. Experiment a little by modeling each of these addition problems.

- 2 + 3
- -1 + (-2)
- 5 + (-3)
- -4 + 2

**Subtraction**

Subtraction is modeled by taking away chips. You will frequently have to add 0 chips (i.e. an equal number of red and black chips) in order to have enough of one kind to take away. Try these problems.

- 5 - 2
- -3 - (-2)
- 3 - 5
- -2 - (-4)

Steve Kifowit Prairie State College Chicago Heights, IL 60411 |