Subtracting Rational Numbers

Subtraction Rules

100

What should I change my subtraction problem to when solving?

Addition

200

What is the first rule when subtracting fractions?

KEEP the first number the same

300

What is the second rule I do when subtracting?

CHANGE to addition

400

What is the third and final thing I do when subtracting?

OPPOSITE of the second number

500

Change this problem to addition.... -3 - (-4), then solve

-3 + 4 = 4 - 3 = 1

Subtracting Integers

100

Solve: 

8-(-2)

8 + 2 = 10

200

Solve: -3 - (- 4) =

- 3 + 4 = 1

300

Solve: 

-5 - 5 =

-5 + -5 = -10

400

SOLVE:   

2 - 9

2 + (-9) = -7

500

SOLVE: 

 -8 - (- 2) =

-8 + (2) = -7

Subtracting Decimals

100

- 3.5 - 4.8 =

-3.5 + (-4.8) = 

-8.3

200

 -5.1 - (-5.1) =

- 5.1 + 5.1 = 

0

300

-5.2 - (-10.5) =

-5.2 + (10.5) = 

5.3

400

 8.9 - (-2.5) =

8.9 + (2.5) = 

11.4

500

18.6 - 11.23 =

18.6 + (-11.23) = 

7.37

Subtracting Fractions

100

2/6 - 1/6 =

2/6 + (-1/6) = 

1/6

200

(-1/5) - 3/5 =

(-1/5) + (-3/5) = 

-4/5

300

1/4 - 5/8 =

1/4 + (-5/8) =

2/8 + (-5/8)=

5/8 - 2/8 =

- 3/8

400

1/2 - (-2/3) =

1/2 + (2/3) =

3/6 + 4/6 = 

7/6 OR 1 and 1/6

500

1 and 2/4 - 1 and 1/6 =

1 and 6/12 + (- 1 and 2/12)

1-1 = 0   

6/12 - 2/12 = 

4/12

Add or Subtract

100

-4 + 12 =

12 - 4 = 8

200

-4.2 + 2.1 =

4.2 - 2.1 = 

-2.1

300

- 5.2 - 10.5 =

-5.2 + (-10.5) = 

5.3

400

-3/5 - 1/2 =

-3/5 + (-1/2) =

6/10 + 5/10 = 

11/10 OR 1 and 1/10

500

1/3 - (-4/5) =

1/3 + (4/5) =

5/15 + 12/15=

17/15 OR 1 and 2/15