Gowshik is going to market from his home by bike at a speed of 20kmph. While he comes back to his home with a speed of X kmph, what should be the value of x so that his average speed is 24kmph ? A) 24 B) 34 C) 30 D) 32

1 Answer

Answer :

C)

Let speed be X

Average speed =2xy/(x+y)

=>2×X×20/(x+20)=24

40x=24x+480

16x=480

X=30 kmph.


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