7th Grade Math

292 Proportions and Similarity

Mid-Chapter

Check

Express each rate as a unit rate. (Lesson 1B)

1. 750 yards in 25 minutes


2. $420 for 15 tickets


3. 42 laps in 6 races


4. MULTIPLE CHOICE In her last race, Bergen
   swam 1,500 meters in 30 minutes. On
   average, how many meters did she swim
   per minute? (Lesson 1B)
   A. 25 C. 40
   B. 30 D. 50


5. Which amount of nuts shown in the table
   has the best unit price? (Lesson 1B)

Weight (oz) Cost ($)

12 2.50

18 3.69

24 4.95

30 6.25

6. ICE CREAM In one 8-hour day, Bella’s Ice
   Cream Shop sold 72 cones of ice cream. In
   one hour, they sold 9 cones of ice cream. Is
   the total number of cones sold in one hour
   proportional to the number of cones sold
   during the day? Explain. (Lesson 1C)


7. DISHES Alan washed 60 plates in 30 minutes.
   It took him 3 minutes to wash 6 plates. Is the
   number of plates washed in 3 minutes
   proportional to the total number of plates he
   washed in 30 minutes? Explain. (Lesson 1C)

Solve each proportion. (Lesson 1D)

8. ^33 r = ^112


9. 36 x = ^1524


10. _^59 = 4.5a
    11. MULTIPLE CHOICE A bread recipe uses 4 cups
    of flour and 2 ^1
    2
    cups of water. If a baker
    puts 24 cups of flour into the mixer,
    how many cups of water will he need?
    (Lesson 1D)
    F. 15 G. 12 H. 8 I. 6
    12. The diagram shows a rectangular patio.
    The length and width of another patio is
    4 times the length and width of the first.
    8 m

6 m

What is the perimeter, in meters, of the

second patio? (Lesson 2A)

13. MAPS Washington, D.C., and Baltimore,
    Maryland, are 2 ^7
    8
    inches apart on a map. If
    the scale is ^1
    2
    inch : 6 miles, what is the
    actual distance between the cities? (Lesson 2B)


14. SCALE DRAWING Each square has a side
    length of _^1
    4
    inch. (Lesson 2B)

,FZ


JO
=

GU

a. What is the actual length of each

window?

b. What are the actual dimensions of the

offi ce space?

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