7th Grade: Operations with Rational Numbers

Because Why Not?

100

The fraction which is equivalent to -.25

- 1/4

200

What are fractions actually doing?

dividing

300

When would you use the "Stay Change Flip" method?

When dividing fractions

400

Define, Reciprocal

The flip of a fraction

500

What are Tuesday's and Wednesday's spirit days this week?

Christmas Out and Ugly Sweater

Adding Rational Numbers

100

1/5 + 3/10

5/10 = 1/2

200

3/7 + (-5/14)

1/14

300

9/50 + (-17/25)

-25/50 = -1/2

400

-5/4 + 1/12

-1 1/6

500

To make a small amount of play dough, you can mix 1 cup of flour, 1/2 cup of salt and 1/2 cup of water. What is the total amount of ingredients added to make the play dough?

2 cups

Subtracting Rational Numbers

100

8/11 - 3/11

5/11

200

- 4/13 - 8/13

-12/13

300

-2/12 - (-1/6)

0

400

-5/12 - (-2/24)

-1/3

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 inches

Multiplying Rational Numbers

100

5(1/3)

1 and 2/3

200

-3 1/5 x 5

-16

300

-1/6 (-2/3)

1/9

400

-3/7 x -5/2

15/14 = 1 1/14

500

Joe had a breakfast party. He invited four of his best friends. Each friend brought 3.4 cups of coffee. How much coffee did they all bring together?

13.6 cups

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 ribbon to make bows for 4 of her friends. How much yard will she use for each ribbon?

5/8 yards

500

List all the properties for adding, subtracting, dividing, and multiplying positives and negatives?

-Add: Same sign? Yes: Add, keep sign OR No: Subtract, sign of biggest number. -Subtract: Keep, change, opposite and use addition rules -Multiply/Divide: Same sign: Answer is positive Different sign: Answer is negative