6th Grade Math Textbook, Progress

Distance, Speed, Time, and Proportion

Speed, or rate (r), is the ratio of distance (d) to time (t).

You can use a proportion to solve for distance or time.

Voyager I travels through space at about

38,600 mph. At that rate, about how far

would Voyager I travel in a half hour?

Voyager I would travel about 19,300 miles in a half hour.

r

38,600 0.5 
 1 d

19,300 
 d

dmi

0.5 h

38,600 mi

1 h

d

t

Use the formula relating distance, speed, and time to write

and solve a proportion.

8. How far will a motorboat travel in 9. A train takes 1 hour to go 75 miles.
   5 h if it travels 35 mi in 1 h? How long will it take the train to go
   450 miles?


9. How long does it take a car to 11. A dragonfly can travel 58 km per
   travel 510 miles at a rate of hour. At this speed, how long would
   68 miles per hour? it take this insect to fly 87 km?


10. Chin delivers 4 newspapers in
    5 min. At this rate, how many
    newspapers can he deliver in
    one hour?


11. A rocket sled traveled a record 15. An electronic car traveled a record of
    of 10 300 km in one hour. At 321.8 mi in one hour. At this rate, how
    this rate, how long would the far would it travel in 15 min?
    vehicle take to travel 2575 km?


12. Catherine spent 2
    1
    2 hours writing
    3 pages of her report. At this rate, how
    long will it take her to write a 15-page
    report?


13. A cake recipe calls for 1.5 cups of
    milk and 3 cups of flour. Ann made
    a mistake and used 5 cups of flour.
    How many cups of milk should she
    use to keep the proportion correct?
    A 1.75 cups B 2.25 cups

C 2 cups D 2.5 cups

17.A rocket car travels at a rate of 640

miles per hour. At this rate, how much

time would it take for the car to travel

384 miles?

F 36 min G 256 min

H245 min J 1.7 h

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