R-SAT
Exam
Numerical Ability
Permutation and Combination
Two trains at start at same time from two stations A and B towards B and A with speeds 72kmph and 90kmph respectively. By the time they meet ,one train covers 64 kms more than other train. what is distance between A and B??
a)512km
b)256
c)576
d)cant be determined
e) none
Read Solution (Total 9)
-
- one train be x km
distance covered one train (x+64) km
x/72=x+64/90
x=256
so, distance between A AND B=(x+x+64)=576 km - 9 years agoHelpfull: Yes(10) No(0)
- Let the distance covered by one train be x km.
Then the distance covered by other train is (64+x)km.
As both the trains started running at the same time , so time taken by them before they meet will be same.
Now ,
T1=T2
or, D1/S1=D2/S2
or, (64+x)/90=x/72
By solving , we get x=256
now The distance between A abd B is = 64+2x=64+2*256=576 (Ans) - 9 years agoHelpfull: Yes(6) No(0)
- Initially suppose, from A to B the train with efficiency 72kmph travelled for 1hr and then
from B to A the train with efficiency 90kmph travelled for 1hr so that the travelled distance by the both the trains is 72kms and 90kms respectively.
In the same way if we notice the travelled distance after 3hrs according to their efficiencies is (72*3=216kms and 90*3=270kms) so the difference becomes 54kms hence the distance in between A ana B is 486kms.ans is none - 9 years agoHelpfull: Yes(5) No(5)
- Initially both train start running towards each other at same time. And one of the train travels 64km more than other train. and the difference between of the trains speed is 18km. and both trains started running at the same time .
Hence time required by each train =64/18
=3.5555hrs
hence Distance traveled by both trains are = (90+722)*3.55555
=576
hence option (c) is correct - 9 years agoHelpfull: Yes(5) No(1)
- one train be x km
distance covered one train (x+64) km
x/72=x+64/90
x=256
so, distance between A AND B=(x+x+64)=576 km
ans:- C - 9 years agoHelpfull: Yes(2) No(0)
- 18-----72+90=162
64-----(162/18)*64=576 - 9 years agoHelpfull: Yes(1) No(0)
- cant be determined
- 8 years agoHelpfull: Yes(1) No(1)
- let 1 train =k km
distance covered one train =x+64km
aftr solving x=256
distance b/w a&b=2(256)+64=576km - 7 years agoHelpfull: Yes(0) No(0)
- C.576
ratio of speeds=4:5
then 1part is 64 then 9 parts is 576. - 7 years agoHelpfull: Yes(0) No(0)
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