Re: GMAT Club Around The World!!! For the convenience of walkers and runne
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31 Dec 2020, 23:09
IMO D
let the length of the track m = 100
markers placed at every fourth of its length => markers will be placed at: {0,25,50,75,100}
markers placed at every fifth of its length => markers will be placed at: {0,20,40,60,80,100}
=> consecutive markers present are present at the locations: {0,20,25,40,50,60,75,80,100}
=> distance between consecutive markers: {20,5,15,0,0,5,5,20}
A. m/10 and m/5 only -Keep
m=100
=> m/10 = 10 --- travel between consecutive markers 40 and 50 or 50 and 60- possible
and m/5=20 --- travel between consecutive markers 0 and 20 or 80 and 100- possible
m/20 and 3m/20 are also possible as mentioned in option D- discard this option
B. m/5 and m/4 only
--- m/10 is also possible - wrong option (calculated in option A)
C. m/20, m/10, m/5, and m/4
m=100
m/20 = 5 -- travel between consecutive markers 25 and 20 - possible
m/4 = 25 -- maximum possible distance between any two markers = 20 --- not possible
D. m/20, m/10, 3m/20, and m/5
m=100
m/20 - possible (verified in option C)
m/10 - possible (verified in option A)
m/5 - possible (verified in option A)
3m/20 - 15 - possible (between markers 80 and 75 or 40 and 25)
Correct
E. m/20, m/10, 3m/20, m/5, and m/4
m=100
m/4 = 25 - not possible (calculated in option C)