Unit Rates and Proportions

During a bake sale,  $1\ \frac{1}{2}$   dozen cookies were sold in  $\frac{1}{3}$   hour. What is the unit rate for the dozens of cookies sold per hour?

•  $4\ \frac{1}{2}$  

•  $\frac{3}{6}$  

•  $\frac{1}{2}$  

•  $\frac{3}{2}$  

Mr. Ruiz drove 305 miles in 5 hours on Saturday and 190 miles in 4 hours on Sunday. What was his average speed, in miles per hour, for the two days?

• 55

• 61

• 47.5

• 110

A candle factory makes colored candle chips to sell in packages. Which of the following situations best represents a proportional relationship?

• Manny sold 109 packages on his first day at work. Gloria sold 100 packages on her first day at work.

• On Monday, 25 packages were prepared every working hour. On Tuesday, 20 packages were prepared every working hour.

• Each individual package is sold for $1.98. Ten packages are sold for $16.99.

• Each package has 8 yellow candle chips. A total of 18 packages will have 144 yellow candle chips.

Which situation below represents a proportional relationship?

• Sandra sold 2 bracelets for $3 and 3 bracelets for $6.

• Jeff ran 4 miles in 20 minutes and 6 miles in 24 minutes.

• Lamont packed 27 glasses in 9 cases and 81 glasses in 27 cases.

• A signal light flashed yellow 7 times in 28 seconds and flashed red 5 times in 35 seconds.

The graph below shows the amount of money Vincent is paid based on the number of hours he works. What is Vincent’s hourly rate of pay?

• 10

• 12

• 15

• 20

Sarah jumps rope to keep in shape. She jumps an average of 20 times in 15 seconds. Find her jumping rate.

• $1.\overline{3}$ jumps per second
  

• 0.75 jumps per second
  

• 2.5 jumps per second
  

• 20 jumps per second
  

Mrs. Woods prepared bags of baked cookies. The graph shows the number of bags and the number of cookies she used. She distributed the cookies evenly throughout all the bags. How many cookies did she use per bag?

• 10

• 4

• 20

• 15

The graph shows data from a science experiment in which the temperature of a substance was measured over time. What is the constant of proportionality for degrees per minute?

• $\frac{1}{4}$

• $\frac{3}{4}$

• $\frac{1}{5}$

• $\frac{2}{3}$

The distance that a typical hummingbird flies is 5.0 meters every second. The graph below models this situation. What does Point J represent on the graph?

• (6, 30)

• (5, 25)

• (4, 20)

• (3, 15)

A store gave all its employees a 20% discount on their purchases. An employee bought a stove that originally cost $678.00. What was the discounted cost of the stove?

• $542.40

• $135.60

• $658.00

• $13,560.00