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Two racecar drivers, Abernathy and Berdoff, are driving around a [#permalink]
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23 Jun 2015, 02:30
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Two racecar drivers, Abernathy and Berdoff, are driving around a [#permalink]
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Updated on: 23 Jun 2015, 22:07
Two racecar drivers, Abernathy and Berdoff, are driving around a circular track. If Abernathy is 200 meters behind Berdoff and both drivers drive at their respective constant rates, how long, in seconds, will it take for Abernathy to catch up to Berdoff?
(1) The circumference of the racetrack is 1,400 meters.
This statement is clearly insufficient as we don't know the speeds of the drivers. Insufficient
(2) Abernathy is driving 25 meters per minute faster than Berdoff.
let Berdoff speed be x meters/minute, Abernathy speed will be x+25 meters/minute
Abernathy and Berdoff are 200 meters apart, so the time taken for Abernathy to catch up to Berdoff = \(\frac{200}{(25+xx)}\)= 200/25= 8 minutes 8*60=480 secnds
sufficient
Ans:B
Originally posted by ManojReddy on 23 Jun 2015, 05:41.
Last edited by ManojReddy on 23 Jun 2015, 22:07, edited 1 time in total.



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Re: Two racecar drivers, Abernathy and Berdoff, are driving around a [#permalink]
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23 Jun 2015, 10:42
Bunuel wrote: Two racecar drivers, Abernathy and Berdoff, are driving around a circular track. If Abernathy is 200 meters behind Berdoff and both drivers drive at their respective constant rates, how long, in seconds, will it take for Abernathy to catch up to Berdoff?
(1) The circumference of the racetrack is 1,400 meters. (2) Abernathy is driving 25 meters per minute faster than Berdoff.
Kudos for a correct solution. Given: Relative Distance between A and B = 200 MetersTime to catch up = Relative Distance / Relative SpeedSo, we require the difference of the speeds of A and B to answer the question. [Relative Speed = Difference of Speeds]Statement 1: The circumference of the racetrack is 1,400 meters.DOesn't provide any information about the Relative SpeedHence, NOT SUFFICIENTStatement 2: Abernathy is driving 25 meters per minute faster than Berdoff.i.e. Relative Speed = 25 Meters per Minute i.e. Time = 200 / 25 = 8 Minutes = 8*60 = 480 Second Hence, SUFFICIENTAnswer: Option
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Re: Two racecar drivers, Abernathy and Berdoff, are driving around a [#permalink]
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23 Jun 2015, 10:45
ManojReddy wrote: Two racecar drivers, Abernathy and Berdoff, are driving around a circular track. If Abernathy is 200 meters behind Berdoff and both drivers drive at their respective constant rates, how long, in seconds, will it take for Abernathy to catch up to Berdoff?
(1) The circumference of the racetrack is 1,400 meters.
This statement is clearly insufficient as we don't know the speeds of the drivers. Insufficient
(2) Abernathy is driving 25 meters per minute faster than Berdoff.
let Berdoff speed be x meters/minute, Abernathy speed will be x+25 meters/minute
Abernathy and Berdoff are 200 meters apart, so the time taken for Abernathy to catch up to Berdoff = \(\frac{200}{(25+x25)}\)= 200/x Since we don't know the value of x, this statement alone is also insufficient. Insufficient
even combining statements 1 and 2, we can't get the individual speeds of Abernathy and Berdoff.
Ans:E Hi ManojReddyPlease check the highlighted part which as mistakeRelative Speed = Speed of A  Speed of BSpeed of B = x Speed of A = x+25 Relative Speed = (x+25)x = 25 meters per Minute
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Two racecar drivers, Abernathy and Berdoff, are driving around a [#permalink]
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23 Jun 2015, 12:37
Bunuel wrote: Two racecar drivers, Abernathy and Berdoff, are driving around a circular track. If Abernathy is 200 meters behind Berdoff and both drivers drive at their respective constant rates, how long, in seconds, will it take for Abernathy to catch up to Berdoff?
(1) The circumference of the racetrack is 1,400 meters. (2) Abernathy is driving 25 meters per minute faster than Berdoff.
Kudos for a correct solution. Statement 1 is irrelevant. The total racetrack is not needed in order to determine how long it will take for Abernathy to catch up to Berdoff. All we need is the difference in Speed between A and B. Insufficient. Statement 2 is sufficient for the above mentioned reason. Therefore Answer B.
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Re: Two racecar drivers, Abernathy and Berdoff, are driving around a [#permalink]
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23 Jun 2015, 22:09
GMATinsight wrote: ManojReddy wrote: Two racecar drivers, Abernathy and Berdoff, are driving around a circular track. If Abernathy is 200 meters behind Berdoff and both drivers drive at their respective constant rates, how long, in seconds, will it take for Abernathy to catch up to Berdoff?
(1) The circumference of the racetrack is 1,400 meters.
This statement is clearly insufficient as we don't know the speeds of the drivers. Insufficient
(2) Abernathy is driving 25 meters per minute faster than Berdoff.
let Berdoff speed be x meters/minute, Abernathy speed will be x+25 meters/minute
Abernathy and Berdoff are 200 meters apart, so the time taken for Abernathy to catch up to Berdoff = \(\frac{200}{(25+x25)}\)= 200/x Since we don't know the value of x, this statement alone is also insufficient. Insufficient
even combining statements 1 and 2, we can't get the individual speeds of Abernathy and Berdoff.
Ans:E Hi ManojReddyPlease check the highlighted part which as mistakeRelative Speed = Speed of A  Speed of BSpeed of B = x Speed of A = x+25 Relative Speed = (x+25)x = 25 meters per Minute It's a miss from my side.. Thanks for correcting. Regards, Manoj Reddy



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Two racecar drivers, Abernathy and Berdoff, are driving around a [#permalink]
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25 Jun 2015, 16:10
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statement 1: insufficient.
statement 2: speed = distance/time 25 =200/t
==> t =8 min = 480 seconds
Sufficient
Answer: B



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Re: Two racecar drivers, Abernathy and Berdoff, are driving around a [#permalink]
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28 Jun 2015, 10:14
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Circular race track! Distance difference/catchup = 200meters! St 1  total circum/distance 1400 meters NS St2 Abernathy is driving 25 meters per minute faster than Berdoff. in 1 min 25 meters more than berdoff in 4 min 100 meters more than berdoff in 8 min 200 meters more than berdoff i.e 8x60=480 sec Suff Answr B



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Re: Two racecar drivers, Abernathy and Berdoff, are driving around a [#permalink]
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29 Jun 2015, 07:22
Bunuel wrote: Two racecar drivers, Abernathy and Berdoff, are driving around a circular track. If Abernathy is 200 meters behind Berdoff and both drivers drive at their respective constant rates, how long, in seconds, will it take for Abernathy to catch up to Berdoff?
(1) The circumference of the racetrack is 1,400 meters. (2) Abernathy is driving 25 meters per minute faster than Berdoff.
Kudos for a correct solution. MANHATTAN GMAT OFFICIAL SOLUTION:This question is much easier than most people assume on first glance! It doesn’t matter that the track is circular— if one driver is 200 meters behind another driver and both drive at constant rates, all you need to know in order to determine the time it takes for the rear driver to catch up is the rate at which the rear driver is “gaining” on the front driver. While of course having the two drivers’ individual rates would be nice, you don’t actually even need that much information— all you need is the rate at which Abernathy is catching up. (When drivers are traveling in the same direction, you subtract their rates; you only need this relative rate.) Thus, the rephrase is, “What is the difference in the two drivers’ rates?” (1) INSUFFICIENT: Knowing the length of the track is insufficient and actually pretty useless, since your math problem really ends at the point that Abernathy catches up to Berdoff. Who cares how much track is in front of them when that happens? (2) SUFFICIENT: This is exactly what you need— if Abernathy is “gaining” at 25 meters per minute, then it will take him 8 minutes to catch up (time = distance/rate, so time = 200/25, which is equal to 8). The answer is (B).
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Re: Two racecar drivers, Abernathy and Berdoff, are driving around a [#permalink]
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29 Jun 2015, 09:38
Bunuel wrote: Two racecar drivers, Abernathy and Berdoff, are driving around a circular track. If Abernathy is 200 meters behind Berdoff and both drivers drive at their respective constant rates, how long, in seconds, will it take for Abernathy to catch up to Berdoff?
(1) The circumference of the racetrack is 1,400 meters. (2) Abernathy is driving 25 meters per minute faster than Berdoff.
Kudos for a correct solution. Time to catch up is Gap / Difference in Speed T = 200/diff in speed State1: Gives the circumference of the track  Not Sufficient State2: Is a direct answer. Hence Sufficient.



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Re: Two racecar drivers, Abernathy and Berdoff, are driving around a [#permalink]
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30 Sep 2015, 22:35
I saw this was a bit different then the question I had..
Two racecar drivers, Abernathy and Berdoff, are driving around a circular track. If Abernathy is 200 meters behind Berdoff and both drivers drive at their respective constant rates, how long, in seconds, will it take for Abernathy to catch up to Berdoff? (1) The circumference of the racetrack is 1,400 meters. (2) Berdoff is driving 25 meters per minute faster than Abernathy.
So
1) Alone NS 2) Alone NS
But C) interesting enough changes the question a bit, since the track is circular it changes the angle and now B is going to lap A and catch up.
The distance between them is now 1200 and the distance is speed in 25
Making B and A together in 2880 seconds?
SO C
IS this right logic?



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Re: Two racecar drivers, Abernathy and Berdoff, are driving around a [#permalink]
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06 Jan 2018, 03:43
Bunuel wrote: Two racecar drivers, Abernathy and Berdoff, are driving around a circular track. If Abernathy is 200 meters behind Berdoff and both drivers drive at their respective constant rates, how long, in seconds, will it take for Abernathy to catch up to Berdoff?
(1) The circumference of the racetrack is 1,400 meters. (2) Abernathy is driving 25 meters per minute faster than Berdoff.
Kudos for a correct solution. I understand that this is an MGMAT question and there was an error in the second statement which is corrected in the question mentioned in this thread. But assuming that there was no error and the question is changed to "how long, in seconds, will it take for Berdoff to catch up to Abernathy?", what would be the ideal way to solve the question?




Re: Two racecar drivers, Abernathy and Berdoff, are driving around a
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