Answer:
Speed of return trip (v) = 60 mph
Step-by-step explanation:
Given:
Distance = x
Speed (u) = 20 mph
Average speed = 30 mph
Find:
Speed of return trip (v)
Computation:
Time taken = Distance / Speed
Time of starting trip = x / 20
Time of starting trip = x / Speed of return trip (v)
Average speed = Total distance / Total time taken
30 = 2(x)/ [x/20 +x / Speed of return trip (v)]
30 = 40 v / (v + 20)
v = 60 mph
Speed of return trip (v) = 60 mph
