A hiker walking at a constant rate

[agha79]

A hiker walking at a constant rate of 4 miles per hour is passed by a cyclist traveling in the same direction along the same path at a constant rate of 20 miles per hour. The cyclist stops to wait for the hiker 5 minutes after passing her, while the hiker continues to walk at her constant rate. How many minutes must the cyclist wait until the hiker catches up?

A. 6 2/3
B. 15
C. 20
D. 25
E. 26 2/3

Rate of hiker in minutes=1/15 miles per minute
Rate of cyclist in minutes=1/3 miles per minute
Cyclist in 5 minutes traveled distance of 5/3 miles (1/3*5)
Hiker travels the same distance in 25 minutes (5*15/3)
So I choose D.

But OA is C.

As the hiker continues to walk while cyclist has crossed her make us deduct the time took by the cyclist to reach at the stopping point. 25-5=20. Is it the rationale behind the actual answer or I made some mistake in calculations?

[RonPurewal]

As the hiker continues to walk while cyclist has crossed her make us deduct the time took by the cyclist to reach at the stopping point. 25-5=20. Is it the rationale behind the actual answer or I made some mistake in calculations?

yes, that's the rationale.
i.e., you weren't reading the problem carefully enough at first -- the problem statement very clearly asks how long the cyclist must wait; the cyclist doesn't start "waiting" until he/she has stopped.