KVPY (Kishore Vaigyanik Protsahan Yojana) StreamSA (Class 11) Math: Questions 1 of 265
» Basic Mathematics » Arithmetic » Ratio and Proportion
Question
Two friends P and Q are 50 km apart and they start simultaneously on cycles to meet each other. The speed of P is 4 times than that of Q. The distance between them decreases at the rate of 2 km per minute. Fifteen minutes after they start, P’s cycle breaks down and P stops and waits for Q to arrive. After how much time (in minutes) P started riding, does Q meet P?
Choices
Choice (4)  Response  

a.  55 

b.  70 

c.  60 

d.  65 

Answer
Explanation
Here from given data speed of P is 4 times that of Q, Therefore if;
Speed of Q = V km/hr
Speed of P = 4V km/hr
The distance between P and Q decreases at the rate of 2 km per minute.
Now, Distance covered by then after 15 min is,
So, remaining distance = (50 – 30) = 20 km
Time taken by Q to cover 20 km is,
Therefore total time is,