HCL
Company
Numerical Ability
Time Distance and Speed
2 frnds A n B running up hill and then to get down length of road-440 yads A on his return journey met B going up at 20 yards from top if A has finished race 5 minute earlier than B then how much time A had taken to complete the race
Read Solution (Total 5)
-
- total journey= 440*2=880
A meet B 20 yards from top in getting down it means he has covered 440+20=460 yards while B is 420 yards.so he is 40 yards ahead of B which is equals to 5 minute.
so 40 yards in 5 min
880 yards will be in 5*880/(40)=110 minute - 11 years agoHelpfull: Yes(23) No(6)
- the ratio is 23/21 and not 23/22
so the ans will be 52.5 mins. - 11 years agoHelpfull: Yes(20) No(5)
- let it take t minutes to meet each other at 20yards from top
at that time a covers 460 yards & b covers 420 yards
let speeds be s1&s2 and t1&t2 are the times taken to complete the race
equating time; (460/s1)=(420/s2)
=> s1/s2= 23/22.........(1)
given b takes 5 more minutes than a
i.e t1+5=t2
finally they cover same distance
so s1*t1= s2*t2
= s2*(t1+5)
(s1/s2)=(t1+5)/t1
from 1
(t1+5)/t1= 23/22
solving t1= 110 minutes
- 11 years agoHelpfull: Yes(16) No(9)
- Time taken by B to cover 40 yads (20up + 20down) = 5 minutes
Therefore,Time Taken to complete 880 yads by B = 110 minutes.
so time taken by A to complete to 880yads = 105 mintues - 11 years agoHelpfull: Yes(2) No(8)
- When A travels 460m (=440+20),
B travels 420m (=440-20). So, ratio of speed = 460:420
= 23:21.
Let A's speed be 23x, and that of B's be 21x.
=> 23x = ((2 * 440) / t) which implies 23t = 880/x;
=> 21x = ((2 * 440) / (t+5)) which implies 21(t+5) = 880/x.
From these two equations, 23t = 21(t+5). Solving, t = 52.5 - 8 years agoHelpfull: Yes(1) No(0)
HCL Other Question