abhishekdadarwal2009 wrote:
Arun, Barun and Kiranmala start from the same place and travel in the same direction at speeds of 30 km/hr, 40 km/hr and 60 km/hr respectively. Barun starts two hours after Arun. If Barun and Kiranmala overtake Arun at the same instant, how many hours after Arun did Kiranmala start?
(A) 3
(B) 3.5
(C) 4
(D) 4.5
(E) 5
Sol speed
A 30
B 40
K 60
Inorder for all of them reach at the same time at the same point. we have to take the LCM
which is 120.
for this distance the time taken by A ,B and K will be 4,3,2 but this does not fit in the questions.
so we take the next point where they may meet which is 240.
the time taken by A,B and K is 7,6 and 4 respectivly.
from this we get hat ther is a difference of 3 hours. Sol A.
Shouldn't it take A 8 hours to travel 240 KM if he's going 30 KM/Hour? So the times would be A=8 B=6 K=4. This lines up if you double the KM from 120 to 240, because then the times will double along with it (4,3,2 ---> 8,6,4)
Therefore the answer is 4 (Sol C)