Inverse Operations

1. Inverse Operations 4th and 5th grade

2. Two operations are said to be Inverse to each other if one operation undoes the effect of the other operation. • Addition and subtraction are inverse operations of each other. • Multiplication and division are inverse operations of each other

3. The inverse operation of • 18 + 10 = 28 is • 28 – 18 = 10. • The inverse operation of • 14 x 3 = 42 is • 42 ÷ 14 = 3.

4. Let’s try a quiz on inverse operations. • What is the correct inverse operation of 400 – 250 = 150 • 400 – 150 = 250 • 400 x 250 = 100,000 • 150 + 250 = 400

5. What answer did you choose? • If you chose, “C” then you were correct. The inverse or opposite of 400 -250 = 150 is 250 + 150 = 400. Let’s try another problem.

6. What is the inverse of this problem? 24 x 3 = 72 a. 72 ÷ 24 = 24 b. 72 ÷ 24 = 3 c . 24 ÷ 3 = 72

7. What answer did you choose? • If you chose answer B, you were correct. The inverse operation of 24 x 3 = 73 is 72 ÷ 24 = 3.

8. 40 + m 76 76 40 36 How would you use the inverse operation of addition to solve this problem?

9. 8 x w = 32 The Inverse operation is 32 ÷ 8 = w w= 4 How would you use the inverse operation to find the answer to the following problem?