The speed at which he walks is 7.7km/hr
The formula for calculating the distance is expressed as;
distance = speed * time
Let the speed moved by the man be x
If the man walks for 2 hours at a certain speed, his distance will be 2x km
If he then cycles at three times that speed for 4 hours, the new the speed at which he walks is 7.7km/hr
If he goes 77km altogether, hence;
2x + 4(2x) = 77
2x + 8x = 77
10x = 77
x = 77/10
x =7.7km/hr
Hence the speed at which he walks is 7.7km/hr
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