Question

A car takes 2 hours to reach a destination by travelling at the speed of 60 km/h. when the car travels at the speed of 80 km/h it takes

• A. one and half hour
• B. one hour
• C. two hour
• D. None

Answer 1

The correct option is A one and half hour

Let the car takes x hours to reach a destination by travelling at the speed of 80 km/h. Then,

Speed (in km/hr)	60	80
Time (in hours)	2	x

Clearly, more the speed, less will be the time taken. So, it is a case of inverse proportion.
$\therefore 60\times 2=80\times x\Rightarrow x=\frac{60\times 2}{80}=\frac{3}{2}$
Hence, the time taken will be $1\frac{1}{2}$ hours.