Question

A car moves 30 km at uniform speed of 60 km/h and the next 30 km at a uniform speed of 40 km/h find the total time taken by the car

Answer 1

distance [1] = 30km

speed [1]    =  60km/h

distance[2]  = 30km

speed[2]      = 40km/h

therefore, in case [1]                         in case[2],                                                            

t= d/s                                                      t=d/s            

 = 30/60= 1/2h                                         = 30/40  = 3/4h

                      total time taken by the car= 1/2+3/4

                                                                   = 5/4 hr