Question 115

Sheela walks a certain distance at (16/17)th of the usual speed and takes 5 minutes more than the usual time. Find the usual time taken. (in minutes)

Solution

Let usual speed = $$17$$ m/min and usual time taken = $$t$$ min

=> New speed = $$16$$ m/min and new time = $$(t+5)$$ min

Also, speed is inversely proportional to time.

=> $$\frac{17}{16}=\frac{t+5}{t}$$

=> $$17t=16t+80$$

=> $$17t-16t=t=80$$

$$\therefore$$ Usual time taken = 80 minutes

=> Ans - (C)