Adding and Subtracting Rational Numbers math7chapter1

Integers

100

-12 + 19

7

200

-15 + -6

-21

300

11 - (-4)

15

400

-2 - (-10)

8

500

5 + (-7) - (-8)

6

Fractions

100

-5/9 + -2/9

-7/9

200

11 8/9 – 6 2/9

5 2/3 or 17/3

300

6 1/3 + (-4 5/6)

1 1/2 or 3/2

400

8 3/4 + -10 2/3

-1 11/12 or -33/12

500

-12 + ¾ - 3/5

-11 7/20 or -227/20

Decimals

100

-26.3 +.26.3

0

200

-15.8 – 15.8

-31.6

300

3.6 + (-1.7)

1.9

400

33.07 + -17.54

15.53

500

-4.4 – (9.6) + 4.4

9.6

Mixed Rational Numbers

100

2.5 + -3/4

1.75 or 1 ¾ or 7/4

200

-4.85 – 7 3/5

-12.45 or -12 9/20 or -249/20

300

19/20 – 0.50 

= 9/20 or 0.45

400

-5.5 + 5 ½  - 6

-6

500

7.34 – 5 ¾ - 10

-8.41 or -8 41/100 or -841/100

Rules

100

Part 1: What is the sign of the sum of two negative numbers?

Part 2: What is the sign of the sum of two positive numbers?

Part 1: negative

Part 2: positive

200

How can you know what the sign will be for the sum of a positive and negative number?

The answer will have the sign of the bigger digit.

300

How do you change a subtraction sentence into an addition sentence?

By adding the opposite.

Keep, Add, Opposite

400

When adding and subtracting fractions, you must have a what?

common denominator

500

When signs are different, you find the (1) __________

of the digits by (2) _______________. 

When signs are the same, you find the (3) ________ of the digits by (4) _______________.

(1) difference

(2) subtracting

(3) sum

(4) adding

Absolute Value

100

2 ____ | -5 | 

2 < | -5 |

200

0.4 ____ |-7/8|

0.4 < |-7/8|

300

- |6| = 

-6

400

Find the distance between -3 and 9 on a number line.

12 units

500

Find the distance between -7.5 and -15.3 on the number line.

7.8