Operations with Rational Numbers

Evaluating Expressions

100

Evaluate the expression for m = 2.5

-m + 6.5 

4

200

Evaluate the expression for x= 8  y=-6

5x + 4y - xy 

64

300

Evaluate the expression for n=3/8.

58n + 8n 

24  3/4

400

Evaluate the expression for a=-3 and b=9.

36 - a²/b   

3

500

Evaluate the expression for a= 4   b= -6  c= 8

-4(2a + cb)

160

Adding Rational Numbers

100

3.15 + 2.25 =

5.40

200

0.38 + (-11.2) =

10.82

300

9/25 + (-17/25) =

-8/25

400

-5/12 + (-8/48) =

-7/12

500

The temperature at 9:00pm is 44 degrees.  The temperature falls 28 degrees and then rises 56.  Use addition to find the change of temperature.  What is the change in temperature and the final temperature?

change:  28 degrees

final temperature:  72 degrees

Subtracting Rational Numbers

100

-84 - (-16) =

-68

200

72 - (-24) = 

96

300

-0.76 - (-3.86) =

3.1

400

-10/11 - (-4/33) =

-26/33

500

The snowfall in Rochester, NY in the winter of 1999-2000 was 91.5 inches. Normal snowfall is about 76 inches per winter. How much more snow fell in the winter of 1999-2000 than is normal?

15.5 

Multiplying Rational Numbers

100

5(1/3) =

1 and 2/3 

200

-3.2 x 5 = 

-16

300

-1/6 (-2/3) =

1/9

400

176(2.3) =

404.8

500

Travis painted for 6 and 2/3 hours. He received $27 an hour for his work. How much was Travis paid for doing this painting job?

$180

Dividing Rational Numbers

100

1/4 divided by 3/8 =

2/3

200

-20 divided by 0.5 =

-40

300

-15 divided by -5/8 =

24

400

Emma bought 2 and 1/2 yards of cording for the trim around the edge of a square pillow. How much will she use for each side of the pillow?

5/8

500

Sean has a loan of $8804.46 including interest. He makes payments of $209.63 each month on the simple interest loan. How many months will it take for Sean to repay his loan?

42 months