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A train leaves Pune at 7 : 30 am and reaches Mumbai at 11 : 30 am. Another train leaves Mumbai at 9 : 30 am and reaches Pune at 1 :00 pm. Assuming that the two trains travels at constant speeds, at what time do the two trains cross each other
option
(A) 10: 20 am
(B) 11 : 30 am
(C) 10 : 26 am
(D) Data not sufficient

Read Solution (Total 1)

Speed of the train, leaving Pune: s_P=PM/4, with PM the distance Pune-Mumbai.

Speed of the train, leaving Mumbai: s_M=PM/3.5.

Train, leaving Pune at 7.30 am, travels a distance PM/4 . 2 till 9.30 am.

At that time, both trains travel a distance PM/2 = s_P.t+ s_M.t = PM/4.t + PM/3.5.t.

Calculating: $t = 56 $minutes. Time of crossing: 9.30 + 0.56.
7 years agoHelpfull: Yes(0) No(2)

KVPY Other Question

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option
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option
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