Question

A man goes to a place on bicycle at speed of 16 km/hr and comes back at lower speed. If the average speed is 6.4 km/hr in total journey, then the return speed (in km/hr) is :

• A. 10
• B. 8
• C. 6
• D. 4

Answer 1

Answer:

D. 4

Average speed : = 2xy/x+y =2×16×y/16+y 6.4=32y/16+y 102.4+6.4=32y ⇒102.4=25.6y ⇒y=102.4/25.6 ⇒y=4 km/hr