A certain race is made up of three stretches: A, B and C, each 2 km long, and to be covered by a certain mode of transport. The following table gives these modes of transport for the stretches, and the minimum and maximum possible speeds (in km/hr) over these stretches. The speed over a particular stretch is assumed to be constant. The previous record for the race is 10 min.
Mr Hare completes the first stretch at the minimum speed and takes the same time for stretch B. He takes 50% more time than the previous record to complete the race. What is Mr Hare's speed for the stretch C?
Total time taken by Mr. Hare to complete the race = 50% more of (10 min.) = 15 min.= $$\frac{1}{4}$$ hr.
Or $$\frac{1}{4} = \frac{2}{40} + \frac{2}{40} + \frac{2}{v}$$ ( i.e. complete time for strech A,B and C Where v is velocity at strech C)
Or v= 13.3 km./hr
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