Ratios
Proportions
Unit Rate
Better Buy
Finding the Unknown
100

Are 3/9 and 4/12 proportional? What are both in lowest terms?

Yes, both fractions can be reduced to 1/3

100

6/19 = 24/x

x = 76

100

A recipe for 6 muffins calls for 360 grams of oats. How many grams of oats are needed for each muffin?

360/6 = 60 grams

100

Which is the better deal?

100 markers for $5.00 or 150 markers for $6.00

$5.00/100 = $0.05

$6.00/150=$0.06

The 100 markers is the better deal because it is cheaper per marker.


100

Two rectangular desks are similar. The larger one is 42 inches long and 18 inches wide. The smaller one is 35 inches long. What is the width of the smaller desk?

42/35 = 18/x

15 inches wide

200

Are 12/15 and 18/24 proportional? What are both in lowest terms?

No, 12/15 can be reduced to 4/5 and 18/24 can be reduced to 3/4.

200

12/21 = x/56

x = 28

200

An airplane flew 2,748 miles in 6 hours? What is the average speed per hour?

458 miles per hour

200

A supermarket sells orange juice in 3 sizes. The 32 fl.oz costs $1.99, the 64 fl. oz costs $3.69, and the 96 fl.oz costs $5.85. Which is the best deal?

$1.99/32 = $0.062 = $0.06

$3.69/64= $0.057 = $0.06

$5.85/96= $0.060 = $0.06

They are the same deal. 

200

Mr. Hemley stands next to the Illinois Centennial Monument at Logan Square in Chicago and casts a shadow that is 18 feet long. The shadow of the monument is 204 feet long. If Mr. Hemley is 6 feet tall, how tall is the monument?

18/204 = 6/x

x = 68 feet tall

300

Are 8/18 and 15/36 proportional? What are both in lowest terms?

No, 8/18 can be reduced to 4/9 and 15/36 can be reduced to 5/12

300

52/104 = 87/x

x=174

300

An after school job pay $116.25 for 15 hours of work. How much is the pay per hour?

$7.75 an hour

300

Candy packages sell for $6.72 for a pack of 6; $8.88 for a pack of 8 and $27.12 for a pack of 24. Which is the lowest price (best buy) per bar?

Pack of 6 - $1.12 per bar

Pack of 8 - $1.11 per bar

Pack of 24 - $1.13

The pack of 8 is the best deal because it is the cheapest price PER BAR.


300

Two picture frames are similar. The length of the first one is 3 inches and the width is 2 inches. The length of the second one is 4.2 inches. What is the width of the second one?

3/4.2 = 2/x 

x=2.8 inches

400

Are 25/35 and 40/56 proportional? What are both in lowest terms?

Yes, both can use reduce to 5/7

400

103/x = 42/84

x=206

400

During exercise, Sonia's heart beats 675 times in 5 minutes. On average, how many times does her heart beat per minute?

675/5 = 135 times per minute

400

Which is the best deal?

450 minutes of phone time for $49.99 or 800 minutes of phone time for $62.99.

49.99/450 = 0.0111 = $0.11 per minute

62.99/800 = 0.078 = $0.08 per minute

400

The official size of a basketball court in the NBA is 94 feet by 50 feet. The basketball court in the school gym is 47 feet long. How wide must it be to be similar to an NBA court?

94/50 = 47/x 

x = 25 feet

500

Are 12/16 and 18/24 proportional? What are both in lowest terms?

Yes, both fractions can be reduced to 3/4

500

80/x = 56/84

x = 120

500

A person walks 1.5 miles in 39 minutes. What is their average speed per mile?

39/1.5 = 26 minutes per mile

500

A supermarket sells orange juice in 3 sizes. The 32 fl.oz costs $1.99, the 64 fl. oz costs $3.69, and the 96 fl.oz costs $5.85. Which is the best deal?

32 fl. oz - $0.062 = $0.06 per fl. oz.

64 fl. oz - $0.057 = 0.06 per fl. oz

96 fl. oz - 0.060 = 0.06 per fl. oz

They all would round to the exact same amount, so they are all the same deal. But typically if you answered the 64 fl.oz you would be correct as well.

500

A 9-foot street sign casts a 12-foot shadow. The lamppost next to it casts a 24-foot shadow. How tall is the lamppost?

9/12 = x/24

18 foot tall