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# Train A traveling at 60 km/hr leaves Mumbai for Delhi at 6 PM. Train B

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Intern
Joined: 30 Mar 2019
Posts: 5
Train A traveling at 60 km/hr leaves Mumbai for Delhi at 6 PM. Train B  [#permalink]

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20 Aug 2019, 12:12
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Difficulty:

55% (hard)

Question Stats:

66% (02:48) correct 34% (03:30) wrong based on 35 sessions

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Train A traveling at 60 km/hr leaves Mumbai for Delhi at 6 PM. Train B travelling at 90km/ he also leaves Mumbai for Delhi at 9 PM. Train C leaves Delhi for Mumbai at 9PM. If all the trains meet at the same time between Mumbai and Delhi, what is the speed of train C if the distance between Delhi and Mumbai is 1260 kms?

A 120 km/hr
B 135 km/he
C 240 km/ hr
D 105 km/ hr
E 90 km/ hr
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Joined: 29 Jun 2019
Posts: 302
Re: Train A traveling at 60 km/hr leaves Mumbai for Delhi at 6 PM. Train B  [#permalink]

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20 Aug 2019, 13:41
90(t-3)=60t
30t=270
t=9,60×9=540
So trains A and B, travel 540 kms of 1260 distance between Delhi and Numbai.
1260-540=720
Because C travels at 9,so
720=6v ==》v=120
Option A

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Re: Train A traveling at 60 km/hr leaves Mumbai for Delhi at 6 PM. Train B  [#permalink]

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20 Aug 2019, 14:04
1
shubhigandhi10 wrote:
Train A traveling at 60 km/hr leaves Mumbai for Delhi at 6 PM. Train B travelling at 90km/ he also leaves Mumbai for Delhi at 9 PM. Train C leaves Delhi for Mumbai at 9PM. If all the trains meet at the same time between Mumbai and Delhi, what is the speed of train C if the distance between Delhi and Mumbai is 1260 kms?

A 120 km/hr
B 135 km/he
C 240 km/ hr
D 105 km/ hr
E 90 km/ hr

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If at distance d from Mumbai they meet and s speed of train C

d/60 = d/90+3 = (1260-d)/s + 3

From 1st eqn, d = 540 km.
so 540/60 = (1260-540)/s +3
=> s = 720/6 = 120kmph
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Re: Train A traveling at 60 km/hr leaves Mumbai for Delhi at 6 PM. Train B  [#permalink]

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20 Aug 2019, 17:01
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1
First, we shall find when & where will B catch up to A:
As A moved 3 hours earlier, the distance between them was 60*3 = 180 km
The time needed by B to catch up to A = $$\frac{180}{90-60} = 6$$ hours
In 6 hours, Train B will have traveled 90*6 = 540 km

So the left distance that Train C should have traveled to meed A & B = 1260 - 540 = 720 km

As train B & C started traveling at the same time, C must have traveled for 6 hours same as B.
so the speed of C = $$\frac{720}{6}$$ = 120 km/h
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Re: Train A traveling at 60 km/hr leaves Mumbai for Delhi at 6 PM. Train B  [#permalink]

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20 Aug 2019, 22:11
shubhigandhi10 wrote:
Train A traveling at 60 km/hr leaves Mumbai for Delhi at 6 PM. Train B travelling at 90km/ he also leaves Mumbai for Delhi at 9 PM. Train C leaves Delhi for Mumbai at 9PM. If all the trains meet at the same time between Mumbai and Delhi, what is the speed of train C if the distance between Delhi and Mumbai is 1260 kms?

A 120 km/hr
B 135 km/he
C 240 km/ hr
D 105 km/ hr
E 90 km/ hr

Given:
1. Train A traveling at 60 km/hr leaves Mumbai for Delhi at 6 PM.
2. Train B travelling at 90km/ he also leaves Mumbai for Delhi at 9 PM.
3. Train C leaves Delhi for Mumbai at 9PM.
4. All the trains meet at the same time between Mumbai and Delhi
5. The distance between Delhi and Mumbai is 1260 kms

Asked: What is the speed of train C ?

Let the speed of train C be x.

1. Train A traveling at 60 km/hr leaves Mumbai for Delhi at 6 PM.
2. Train B travelling at 90km/ he also leaves Mumbai for Delhi at 9 PM.

Train A travel from 6PM to 9PM = 60 *3 = 180 km

4. All the trains meet at the same time between Mumbai and Delhi
Train A & Train B meet at = 180/(90-60) = 6 hours after 9PM
Train B travels = 90*6 = 540 km from Mumbai to Delhi at the time of meeting.

5. The distance between Delhi and Mumbai is 1260 kms
Train distance travelled by train C from Delhi to Mumbai = 1260 - 540 = 720 km
Time taken by train C = 6 hours
Speed of train C = 720/6 = 120 kmh

IMO A
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Re: Train A traveling at 60 km/hr leaves Mumbai for Delhi at 6 PM. Train B   [#permalink] 20 Aug 2019, 22:11
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