Question

The distance between two places is 120 km. A car travelling at a certain speed can combe
the distance in 2 hours 30 minutes. By how many kmh should the speed of the car be
Increased for it to take 30 minutes less to cover the distance?​

Answer 1

Answer:

12km/hr

Step-by-step explanation:

Distance between two places=120 km

Time= 2 hrs 30 min

       =(2*60)min+30 min

       =120 min+30 min

       =150 min=150/60 hr

        = 5/2 hr

Speed = distance /time

          = (120/5/2)km/hr

          =(120×2/5)km/hr

          =(240/5)km/hr

          = 48 km/hr

New time = 2hr 30min-30min

               = 2hr

Distance =120km

Speed  = Distance /time

           =120/2 km/hr

           = 60 km/hr

Increase in speed=(60-48)km/hr  

                            =12km/hr