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A, B and C run around a circular track starting from the same point
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22 Jul 2016, 03:53
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A, B and C run around a circular track starting from the same point simultaneously and in the same direction at speeds of 4 kmph, 6 kmph and 8 kmph respectively. If the length of the track is 400 meters, when will A, B and C meet at the starting point for the first time after they started the race? A. 1 minute B. 5 minutes C. 12 minutes D. 20 minutes E. 24 minutes
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A, B and C run around a circular track starting from the same point
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22 Jul 2016, 04:09
take lcm of 4,6,8
24
ans E
till that time A will have 6 revs b will 4revs and c will have 3 revs



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A, B and C run around a circular track starting from the same point
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22 Jul 2016, 04:49
4 kmph, 6 kmph and 8 kmph is equal to 4000/60 mtrs/min, 6000/60 mtrs/min and 8000/60 mtrs/min or 200/3, 100, 400/3 mtrs/min respectively.
Seeing this we can infer that the answer should be at least divisible by 3. (minutes in options are integers. So if the answer is not divisible by 3, we will have 200/3*answer = distance traveled by A in fractions whereas 100*answer = distance traveled by A as integer)
So, A,B and D are out.
At 12 min A,B and C will travel 800, 1200 and 1600 mtrs respectively. Length of the circle is given as 400 mtrs.
As 800, 1200 and 1600 are divisible by 400, we can say that A,B and C will be at starting point after 12 min.
Hence, C will be the answer.



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Re: A, B and C run around a circular track starting from the same point
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22 Jul 2016, 08:41
hsbinfy wrote: take lcm of 4,6,8
24
ans E
till that time A will have 6 revs b will 4revs and c will have 3 revs we are given values in hour & answers in mins do convert Ans 12



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Re: A, B and C run around a circular track starting from the same point
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22 Jul 2016, 08:55
A: 400 metres in 6 minutes B: 400 metres in 4 minutes C: 400 metres in 3 minutes
LCM? 12
Answer C)



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Re: A, B and C run around a circular track starting from the same point
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22 Jul 2016, 09:54
time taken by A ,B and C to complete a round will be 6,4,3 mins respectively. LCM of 6,4,3= 12 so they will meet at starting point after 12 mins
ANS C



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Re: A, B and C run around a circular track starting from the same point
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28 Jul 2016, 11:12
gauravsaggis1 wrote: time taken by A ,B and C to complete a round will be 6,4,3 mins respectively. LCM of 6,4,3= 12 so they will meet at starting point after 12 mins
ANS C Hi! Can you please explain, how did u get 6, 4 and 3. Thanks



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Re: A, B and C run around a circular track starting from the same point
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28 Jul 2016, 13:36
Bunuel wrote: A, B and C run around a circular track starting from the same point simultaneously and in the same direction at speeds of 4 kmph, 6 kmph and 8 kmph respectively. If the length of the track is 400 meters, when will A, B and C meet at the starting point for the first time after they started the race?
A. 1 minute B. 5 minutes C. 12 minutes D. 20 minutes E. 24 minutes Respective speed of A, B and C= 4000/60 , 6000/60, 8000/60 km/h Time required by A= 400 *60/4000= 6 mins Time required by B= 400*60/6000= 4 mins Time required by C = 400 *60/8000= 3 mins Time when these three first meet= LCM of 6, 4 and 3= 12 mins C is the answer
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Re: A, B and C run around a circular track starting from the same point
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14 Aug 2016, 05:53
how can you solve the same with the table given in the Gmat club math book



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Re: A, B and C run around a circular track starting from the same point
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25 Oct 2018, 02:39
Please suggest if my method to solve this question is right.
Distance is same for A, B and C= 400 meters. Since they are going in same direction, relative speed can be calculated: 864= 2kmph
Time = (400/2*1000)*60= 12 min.



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29 Jan 2019, 02:21
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Re: A, B and C run around a circular track starting from the
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