Question

A car moves with a speed of 40km /h for 15 minutes and then with a speed of 60km/h for the next 15 minutes. Find the total distance covered by the car in this 30 minutes

Answer 1

speed in first time of a car =40 km per hour 40×5/18 =100/9 m per second .now time =15 min =15 ×60 =900 sec . distance = speed × time so,=100/9 ×900 =10000 metre.now in next time speed of car =60 km per hour = 60 ×5/18 =50/6 m per sec.time = 15 min again =15×60=900 sec
=distance =speed ×time=50/6×900 =150×50 =7500 m. now total distance = 10000+7500 =17500 metres.