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Operations III
Inverse Operations: Addition and Subtraction
Inverse operations are mathematical
operations that undoeach other.
Addition and subtraction are inverse operations.
Let a, b,and cbe any numbers.
If abc, then cba. If cba, then abc.
Subtraction “undoes” addition. Addition “undoes” subtraction.
Find the missing number.
x 5 12
x 12 5
x 7
Think
7 5 12 and
12 5 7 are
related sentences.
Find the missing number.
x 9 15
x 15 9
x 24
Think
24 9 15 and
15 9 24 are
related sentences.
Multiplication and division are also inverse operations.
Let a, b,and cbe any numbers.
If abc, then cba. If cba, then abc.
Division “undoes” multiplication. Multiplication “undoes” division.
Find the missing number.
y 4 12
y 12 4
y 3
Think
3 4 12 and
12 4 3 are
related sentences.
Find the missing number.
y 6 18
y 18 6
y 108
Think
108 6 18 and
18 6 108 are
related sentences.
Find the missing number using inverse operations.
- 8 a 12 2. 36 b 9 3. r$2.96$10.00
- n 40 56 5. 19 d 418 6. y 3 233
- 45 a 675 8. 23 c$115.00 9. e 468 9921
- 99,999f 9898 11. g 321 123 12. $101.00 2 h
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