• ratio

• rate

• unit rate

• Express ratios as fractions in simplest form and determine unit rates.

Write Ratios in Simplest Form

Express 12 blue marbles out of 18 marbles in simplest form.

Divide the numerator and denominator by the greatest common factor, 6. Divide out common units.

Answer:

A. A

B. B

C. C

D. D

A B C D

0% 0%0%0%

Express 5 blue marbles out of 20 marbles in simplest form.

A.

B.

C.

D.

Write Ratios in Simplest Form

Express 10 inches to 2 feet in simplest form.

Convert 2 feet to 24 inches.

Divide the numerator and denominator by 2. Divide out common units.

Answer:

Lesson 1 CYP2

1. A

2. B

3. C

4. D

0%0%0%0%

A B C D

Express 14 inches to 2 feet in simplest form.

A.

B.

C.

D.

Find a Unit Rate

READING Y-Mei reads 141 pages in 3 hours. How many pages does she read per hour?

Write the rate that expresses the comparison of pages to hours. Then find the unit rate.

Answer: Y-Mei reads an average of 47 pages per hour.

Divide the numerator and denominator by 3 to get a denominator of 1.

1. A

2. B

3. C

4. D

0%0%0%0%

A B C D

A. about 57 mph

B. about 60 mph

C. about 62 mph

D. about 65 mph

TRAVEL On a trip from Columbus, Ohio, to Myrtle Beach, South Carolina, Lee drove 864 miles in 14 hours. What was Lee’s average speed in miles per hour?

SHOPPING Alex spends $12.50 for 2 pounds of almonds and $23.85 for 5 pounds of jellybeans. Which item costs less per pound? By how much?

Answer: The almonds cost $6.25 per pound, and the jellybeans cost $4.77 per pound. So, the jellybeans cost $6.25 – $4.77 or $1.48 per pound less than the almonds.

Compare Unit Rates

For each item, write a rate that compares the cost of the item to the number of pounds. Then find the unit rates.

A. A

B. B

C. C

D. D

A B C D

0% 0%0%0%

A. cashews by $0.90

B. cashews by $1.25

C. macadamia nuts by $0.90

D. macadamia nuts by $1.25

SHOPPING Cameron spends $22.50 for 2 pounds of macadamia nuts and $31.05 for 3 pounds of cashews. Which item costs less per pound? By how much?

• proportional

• nonproportional

• Identify proportional and nonproportional relationships.

Identify Proportional Relationships

HOUSE CLEANING A house-cleaning service charges $45 for the first hour and $30 per hour for each additional hour. The service works for 4 hours. Is the fee proportional to the number of hours worked? Make a table of values to explain your reasoning.

Find the fee for 1, 2, 3, and 4 hours worked and make a table to display numbers and cost.

Identify Proportional Relationships

For each number of hours, write the relationship of the fee and number of hours as a ratio in simplest form.

Answer: Since the ratios of the two quantities are not the same, the fee is not proportional to the number of hours worked. The relationship is nonproportional.

,

1. A

2. B

0%0%

A. yes

B. no

PLUMBING A plumbing company charges $50 for the first hour and $40 for each additional hour. Suppose a service call is estimated to last 4 hours. Is the fee proportional to the number of hours worked?

Identify Proportional Relationships

Find the amount of jelly and egg whites needed for different numbers of servings and make a table to show these measures.

Identify Proportional Relationships

For each number of cups of jelly, write the relationship of the amount of jelly to the number of egg whites as a ratio in simplest form.

Answer: Since the ratios between the two quantities are

all equal to , the amount of jelly used is proportional to

the number of egg whites used.

1. A

2. B

0%0%

A. yes

B. no

COOKING Among other ingredients, a chocolate chip cookie recipe calls for 2.5 cups of flour for every 1 cup of sugar and every 2 eggs. Is the amount of flour used proportional to the number of eggs used?