With a speed of 48 km/h Raghu is able to complete his journey in 2 hours 32 minutes.  If he wants to cover the same distance in 1 hour 36 minutes, then what will be the speed?

76 km/h

t = 2 hours 32 minutes  =  2 + \(\frac{32}{60}\) = 2 + \(\frac{8}{15}\) = \(\frac{38}{15}\)

D = 48 × \(\frac{38}{15}\) = 16 × \(\frac{38}{5}\)

t = 1 + \(\frac{36}{60}\) = 1 + \(\frac{3}{5}\) = \(\frac{8}{5}\)

New speed, 

S = \(\frac{16 × 38 × 5}{5 × 8}\) = 76 km/h