A car left 60 minutes early than the scheduled tie but in order to reach its destination 280 km away in time, it has to slow its usual speed by 14 km/hr. What is the usual speed of the car ?

70 km/hr

Let usual speed = S

According to question ,

\(\frac{280}{S}\) - \(\frac{280}{S-14}\)  = 1

\(\frac{280(S-14) - 280S}{S(S-14)}\) = 1

On solving ,

S = 70

Usual speed is 70km/h.