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(#M40032669) INFOSYS Numerical Ability question Keep an EYE

what ARE THE SPEEDS OF two trains travels with 80 yards and 85 yards long respectively?assume that former is faster than lather
a)they take 75 secto pass eachother inoppp direction b)they take 37.5 seconds to pass each other in same direction

Asked In Infosys (11 years ago)

Solved Snehasis Read Solution (6)

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Read Solution (6) :

Snehasis  (11 years ago)

Sorry friends this is my little correction to the previous solution....this is the correct one.

let the speeds be x and y

when moves in same direction the relative speed, x-y = 85-80/37.5 = 0.13 .....(l)

when moves in opposite direction the relative speed, x+y = 165/75 = 2.2...(ll)

now, equation l + equation ll gives, 2x = 0.13+2.2 = 2.33 => x=1.165

from equation l, x-y=0.13 => y = 1.165-0.13 = 1.035

therefore the speeds are 1.165 yards/sec and 1.035 yards/sec.

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sayantan chatterjee  (11 years ago)

I think this question is not correct as because passing in same direction always takes much time than passing in opposite direction.

Is this solution Helpfull? Yes (13) | No (2)  

ashique khan  (11 years ago)

in opposite direction--
their average speed would be=v1+v2=(80+85)/75 sec
in same direction---
their average speed would be= v2-v1=165/37.5=(165*2)/75 sec v2>v1

now 2v2=3*165/75; v2=33/10=3.3 yards/sec
v1=165/750=1.1 yards/sec


ok though the question is wrong but the process would be like this.

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Snehasis  (11 years ago)

let the speeds be x and y

when moves in same direction the relative speed, x-y = 85-80/37.5 = 0.13 .....(l)

when moves in opposite direction the relative speed, x+y = 165/75 = 2.2...(ll)

now, equation l + equation ll gives, 2x = 0.13+2.2 = 2.33 => x=1.165

from equation l, x-y=0.13 => y = 1.165-2.33 = 1.035

therefore the speeds are 1.165 yards/sec and 1.035 yards/sec.

Is this solution Helpfull? Yes (3) | No (7)  

suguru anusha  (11 years ago)

3.3y/s & 1.1y/s

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tirupathi reddy  (10 years ago)

I have a doubt
When the trains are in opp direction they meet in less time than in same direction
Can any one explain me....thank u in advance

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