The correct answer is 176
9514 1404 393
Answer:
a. 0.6 h
b. 1.3 h
c. C -- No
d. 4.2 mi/h
Step-by-step explanation:
a. The relationship between time (t), speed (s), and distance (d) is ...
t = d/s
The time spent running 4 miles at 7 miles per hour is ...
t = (4 mi)/(7 mi/h) = (4/7) h ≈ 0.6 h
__
b. The time spent walking home is ...
t = (4 mi)/(3 mi/h) = 4/3 h ≈ 1.3 h
__
c. C -- No, less time is spent at 7 mi/h
__
d. The average speed is ...
s = d/t = (4 mi +4 mi)/(4/7 h +4/3 h) = (8 mi)/(40/21 h) = 4.2 mi/h
