Question

A car moves with a speed of 40 km/hr for 15 minutes and then with a speed of 60 km/hr for the next 15 minutes. What is the total distance covered by the car? Also, find the average speed of the car. [5 MARKS]

Answer 1

Steps: 1 Marks
Distance: 2 Mark
Average Speed: 2 Mark

15 minutes $=\frac{15}{60}hrs=0.25hrs$

Distance covered in first 15 minutes $=speed\times time$

$=40\times 0.25=10km$

Speed of car changes to 60 km/hr and it travels for another 15 min.

Distance covered in next 15 minutes $=speed\times time$

$=60\times 0.25=15km$

Total distance covered in 30 minutes = 10 + 15 = 25 km

Average speed $=\frac{TotalDistance}{Totaltime}$
$=\frac{25}{0.5}$
= 50 km/hr