A man drives to town 30 miles away at a speed of 45 mph and arrives in 40 mins. On his return, he takes 60 mins. What is his average speed for the total trip?

Question

A man drives to town 30 miles away at a speed of 45 mph and arrives in 40 mins. On his return, he takes 60 mins. What is his average speed for the total trip?

A. 164

B. 156

C. 155

D. 152

Answer: B

Solution:

= (12 x 8) + (6 x 14) – (2 + 8 + 10 + 4)

= (96) + (84) – (24)

= 156