Correct Answer: 4.14 kmph
Explanation:
A's speed = (5*5/15)m/sec = (25/18)m/sec
Time taken by A to cover 100 m = (100*18/15)sec = 72sec
Time taken by B to cover 92 m = (72 + 8) = 80 sec.
B's speed =(92/80*18/5)kmph =4.14kmph