In a race between A and B, both start simultaneously from the same poi

Question

In a race between A and B, both start simultaneously from the same point but A runs clockwise and B runs anticlockwise. They meet for the first time at a distance of 300 meters clockwise from the starting point and for the second time at a distance of 200 meters anticlockwise from the starting point. Find the ratio of speeds of A and B, if it is known that A has not completed one full round until the second meeting.

A. 3 : 2
B. 1 : 1
C. 3 : 5
D. 1 : 3
E. Cannot be determined

Are You Up For the Challenge: 700 Level Questions

A. 3 : 2
B. 1 : 1
C. 3 : 5
D. 1 : 3
E. Cannot be determined

Are You Up For the Challenge: 700 Level Questions

effatara · Answer

Let the circumference of the track be 'c' meters.

A travels 300 meter and B travels (c-300) meter to their first meeting.
Speed of A (SA)/Speed of B (SB) = 300/(c-300)

A then travels (c-500) meters and B travels (300+200=500) meters to their 2nd meeting
SA/SB = (c-500)/500

300/(c-300)=(c-500)/500...> d^2-00=0...> d(d-800)=0...> d=800. Therefore, after starting A and B travel for 300 meters and (800-300=500) meters respectively to their 1st meeting. Therefore, SA/SB=300/500=3/5.

ANS: C

mimundertaker · Answer

a quicker way to solve I think is

if at the first meeting point:
because time for both is equal, distance is in the ration of speed which is: A/B=300/x-300
so basically, 
if A travels 300 out of x, then A will travel 600 out of 2x.

let's consider the second meeting point now - 
A has travelled: x-200
B has travelled: x+200
together they've travelled: x-200+x+200 = 2x
so A has travelled x-200 out of 2x.

Equate what we know from earlier: x-200=600 >>> x=800
so A/B = 300/800-300 = 3/5

providentducimus · Answer

hey Bunuel can you explain this

Krunaal · Answer

Thanks for posting, and welcome to GMATClub. It'd be great if you can share any particular part of the question, or above explanations that you did not follow, that way it helps the expert to address your doubt specifically.

In a race between A and B, both start simultaneously from the same poi

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