Jack enters a lift on the 23rd floor, which is going up @ 18 floors/min speed. At the same time Jill

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13 May 2019 Lift

Jack enters a lift on the 23rd floor, which is going up @ 18 floors/min speed. At the same time Jill

enters another lift on the 183rd floor which is going down @ 27 floors/min speed. At what floor will they be together?

OPtion

1) 64
2) 65
3) 67
4) 41
5) 43
6) 47
7) 97
8) 93
9) 95
10) None of these

Solution

Relative Speed = 18+27 = 45 floors/min
Relative Distance = 183 - 23 = 160 floors

Time to cover 160 floors with relative speed = 160*60/45 = 640/3 seconds

Floors travelled by Jack in 640/3 seconds = (18/60)*640/3 = 64
Floors on which they will meet = 23 + 64 = 87th
Option 10)

Correct Option: 10 Best Solution (0)