1. Which expression calculates the speed in meters per second of an object that travels a distance of 100 m every 20 s?

100⋅20

10020

100+20

100−20


2.How long would it take to travel 315 mi at the rate of 45 mi/h ?


7 h

270 h

360 h

14,175 h


3.A boat travels for 4 hours at a constant speed of 35.25 km/h.


How far does the boat travel?


105 km

120 km

141 km

352 km


4.Anton's family drove 216 mi to the lake averaging 48 ​ mi/h ​ . On the return trip home they averaged 54 mi/h .


What was the total time that Anton's family spent driving to and from the lake?


8.0 h

8.5 h

9.0 h

9.5 h

  1. a delivery truck drove 203 mi in 3.5 h. After unloading and loading new cargo, it traveled on another 243 mi for 4.5 h.

What was the average speed of the truck over its entire route?


Round to the nearest hundredth, if necessary.


55.75 mi/h

56.00 mi/h

58.00 mi/h

63.70 mi/h







Verified Answer :

  1. 100 * 20
    2. 7 hours
    3. 141 kilometers
    4. 8.5 hours
    5. 55.75 mi/h

Answer:

1. 100/20

2. 7 h

3. 141 km

4. 8.5 hours

5. 56 mi/h

Step-by-step explanation:

(dimensions are omitted)

1. speed = distance/time

speed = 100/20

2. time = distance/speed

time = 315/45 = 7 h

3. distance = speedtime

distance = 35.25 4 = 141 km

4. time = distance/speed

to the lake: time = 216/48 = 4.5 h

from the lake: time = 216/54 = 4 h

total time:  4.5 + 4 = 8.5 h

5. speed = distance/time

first trip: speed = 203/3.5 = 58 mi/h

second trip: speed = 243/4.5 = 54 mi/h

average speed = (58 + 54)/2 = 56 mi/h