cleetus wrote:
Three runners A,B and C run a race with A finishing 20 m ahead of B and 34 m ahead of C, while B finishes 21 m ahead of C. Each runner travels the entire distance at a constant speed. What was the length of the race.
A) 40 m
B) 50 m
C) 60 m
D) 80 m
E) 90 m
Since A finishes 20 meters ahead of B, the distance traveled by B in B's final leg = 20 meters.
Since the remaining distance for C decreases from 34 meters to 21 meters, the distance traveled by C during B's final leg = 34-21 = 13 meters.
Thus, the distance ratio for B and C = \(\frac{B's-distance}{C's-distance}\) = \(\frac{20}{13}\) =
\(\frac{60}{39}\).
In the green fraction, B's distance - C's distance = 60-39 = 21 meters.
Implication:
For B to finish 21 meters ahead of C, B must travel a TOTAL DISTANCE OF 60 METERS, while C travels only 39 meters.
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