# If A had walked at double the speed, how much time he would have taken to reach the destination?

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The ratio between the rates of walking of A and B is 2:3 and therefore A takes 10 minute more than the time taken by B to reach the destination.

If A had walked at double the speed, how much time he would have taken to reach the destination.

posted Sep 23, 2015

15 min
i.e
assume the same distance, d; then
d/tA : d/tB =2:3

d/tA * tB/d =2/3
tB/tA = 2/3
tA = 3/2tB................1
but tA = tB +10min

tB = 20min and tA = 30min
at double speed, eqn 1 becomes
tA = 3/4tB.
but tB is unchanged, which is 20min

tA = 15min

probably 4:3

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