Question

A car running at a speed of 48 kmph on an average, covers a certain distance in 100 minutes. The speed at which the car must run to reduce the time of journey to 40 min will be:

• A. 120 kmph
• B. 240 kmph
• C. 180 kmph
• D. 80 kmph

Answer 1

The correct option is A

120 kmph

Time = $\frac{100}{60}$ = $\frac{5}{3}$ hrs

Speed = 48 kmph

Distance = speed $\times$ time
= 48 $\times$ $\frac{5}{3}$
= 80 km

Now, new time = 40 min = $\frac{2}{3}$ hrs
New speed = $\frac{80}{\frac{2}{3}}$
= $\frac{240}{2}$
= 120 kmph