- Two friends A and B run around a circular track of length 510 metres,
starting from the same point, simultaneously and in the same direction. A
who runs faster laps B in the middle of the 5th round. If A and B
were to run a 3 km race long race, how much start, in terms of distance,
should A give B so that they finish the race in a dead heat?
(1) 545.45 metres (2) 666.67 metres (3) 857.14 metres (4) Cannot be determined
Solution:
A and B run around a circular track. A laps B in the middle of the 5thlap. i.e. when A has run four and a half laps he has covered a distance which is 1 lap greater than that covered by B's.
Therefore, when A runs 9/2 laps, B runs 7/2 laps.
Which is the same as saying when A runs 9 laps, B runs 7 laps.
i.e in a race that is 9 laps long, A can give B a start of 2 laps.
So, if the race is of 3000 metres long, then A can give B a start of 2/9 * 3000= 666.67 metres.
The information with regard to the length of the circular track is redundant information.
