B starts 4 minutes after A from the same point, for a place at a distance of 7 miles from the starting point. A on reaching the destination turns back and walks a mile where he meets B. If A’s speed is a mile in 8 minutes then B’s speed is a mile in how many minutes?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 10
Speed of A = 1 mile/8 minutes
= 7.5 miles/hrs
Speed of B = x miles/hrs
Total distance covered by A = 8 miles
Time taken by A = 64 minutes
B starts 4 minutes later,
Time taken by B = 60 minutes
Distance covered = 6 miles
Speed = 60/6 = 10 minutes/mile