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Two men start together to walk a certain distance, one at 4 km/h and another at 3 km/h. The former arrives half an hour before the latter. Find the distance(in km).
Let the time taken by the man travelling at 4 km/h be t hours, then the time taken by the man travelling at 3 km/h will be (t+12) hours
As the distance travelled by them is same then the speed will be inversely proportional to the time taken.
43=t+12t
4t=3t+32
t=32 hours
The man travelling at 4 km\h travels for 32 hours hence the distance will be 4×32=6km