A car takes 2 hours more to cover a distance of 480 km when its speed is reduced by 8 kmph. Find its usual speed

48 kmph

Formula used here is :-

Speed = \(\frac{Distance}{Time}\)

Let us consider that usual speed = s km/h

According to question ,

\(\frac{480}{ s - 8 }\) - \(\frac{480}{ s }\) = 2

\(\frac{480s - 480s + 3840}{ s (s - 8)}\) = 2

\(\frac{ 1920}{ s (s - 8)}\) = 1

1920 = s ( s - 8 )

s² - 8s - 1920 = 0

s² + 40s - 48s - 1920 = 0

On solving it

s = 48 km/h

So, Usual speed is = s km/h = 48 km/h