Question

suppose you run 5 miles from your house to a friends house at a speed of 7 miles per hour. when the time comes to return home, you are tired and walk the sam 5 miles home at 3 miles per hour. complete parts a through d below

Answer 1

a-

$Time=\frac{Distance}{Speed} =\frac{5}{7} = 0.7 hour$

b-

$Time=\frac{Distance}{Speed} =\frac{5}{3} = 1.7hour$

c-

Correct answer = A- No, because less time is spent travelling 7 miles per hour

d-

$Average \ speed = \frac{2ab}{(a+b)}$

a= Speed at which you run from your house to your friends house = 7 mph

b= Speed at which you walk from your friends house to your house = 3 mph

$Average \ speed = \frac{(2)(7)(3)}{7+3} = \frac{42}{10} = 4.2 mph$