Question

Delhi to Chandigarh journey of 192 km takes 2 hours less if Sumeet travels by his own car than If he travels by bus whose average speed is 16 km/hr less than that of his car. Determine speed of car.

• A. $48$
• B. $32$
• C. $16$
• D. None

Answer 1

Answer: (A)

$48$

Let average speed = x
Av. speed of bus = x-16
Time taken by car = $\frac{192}{x}$

Time taken by bus $=\frac{192}{x-16}$
$\frac{192}{x-16}=\frac{192}{x}+2,192x=192x-3072+{2x}^2-32x$
$x^2-16x-1536=0$
$x^2-48x+32x-1536=0$
$(x+32)(x-48)=0$
$x=48$