1. Chapter 4 and 5
Study Guide

2. Write the ratios.
1. There are 28 video discs and 9 music discs on a shelf. The ratio of the number of video discs to the number of music discs is ____ : ____
2. A bag contains 4 red cards and 7 blue cards. The ratio of the number of red cards to the total number of cards is ____ : ____
Express the ratios in simplest form.
: : : 48
____ : ____ ____ : ____ ____ : ____ 28 9 4 11 21 5 9 13 1 4

3. Write the missing term in each pair of equivalent ratios.
: : : 9
12: ____ : ____ ____ : 27
State whether each statement is expressed as a unit rate.
11. A wheel makes 72 revolutions per minute. ______
12. Ling paid $3.50 for 2 notebooks.______ 23 18 24
yes no

4. A photocopy machine can print 735 copies in 7 minutes
A photocopy machine can print 735 copies in 7 minutes. What is the unit rate at which the machine prints the copies?
7 minutes = 735 copies 1 minute = 735 ÷ 7 = 105 copies The machine prints copies per minute.
105

5. A wooden plank is cut into two pieces
A wooden plank is cut into two pieces. The ratio of the length of the two pieces of wood is 7 : 10. If the length of the two pieces total 952 centimeters, what is the length of the shorter piece of wood?
Piece 1: Piece 2: 17 units = 952 centimeters 1 unit = 952 ÷ 17 = 56 centimeters 7 units = 7 x 56 = 392 centimeters The shorter piece is centimeters.
952 centimeters
392

6. 15. Sunnybrook Orchard grows three types of trees: orange, apple, and pear. There is a total of 1,200 trees in the orchard. The ratio of the number of orange trees to the number of apple trees is 5 : 6. If there are 300 orange trees, how many pear trees are there?
300
Orange: Apple: Pear: 5 units = 300 trees 1 unit = 300 ÷ 5 = 60 trees 6 units = 6 x 60 = 360 apple trees There are pear trees.
1,200 trees ??
1200
300
360
540
540

7. Box It Baby.
16. Cereal A costs $4.90 for a 14-ounce box and Cereal B costs $3.84 for a 12-ounce box. Determine which cereal is the better buy? Explain how you determined your answer. (2 points)
Determine Better Buy
Explain how you determined answer
Cereal A:
14 oz → $4.90
1 oz → $4.90 ÷ 14 = $0.35 per ounce
I calculated the unit rate for both cereals and found Cereal B is cheaper per ounce.
Cereal B:
12 oz → $3.84
1 oz → $3.84 ÷ 12 = $0.32 per ounce
Answer Statement:
Cereal is the better buy. B

8. Box It Baby.
17. Identify which type of fruit costs the most per pound? What is the price difference per pound between the most expensive fruit and the cheapest fruit? (2 points)
Identify which type costs most per pound
What is price difference between most expensive and cheapest
Cherries: $5.99 per pound
Grapefruit:
15 lb → $11.70
1 lb → $11.70 ÷ 15 = $0.78 per lb
5.99
0.78
5.21
Rhubarb:
3 lb → $14.97
1 lb → $14.97 ÷ 3 = $4.99 per lb
cost the most per pound. The difference between the most expensive and least expensive fruit is $ per pound.
Answer Statement:
Cherries
5.21