A car moves with a speed of 40 km/h for 15 minutes and then with a speed of 60 km/h for the next 15 minutes. The total distance covered by the car is:

(i) 100 km (ii) 25 km (iii) 15 km (iv) 10 km

(ii) 25 km

Case I

Speed of the car = 40 km/h

Time taken = 15 min =15/60= 0.25h 

Distance covered, d₁ = Speed × Time taken = 40 × 0.25 = 10 km

Case II

Speed of the car = 60 km/h

Time taken = 15 min =15/60= 0.25h 

Distance covered, d₂ = Speed × Time taken = 60 × 0.25 = 15 km

Total distance covered by the car, d = d₁ + d₂ = 10 + 15 = 25 km

Therefore, the total distance covered by the car is 25 km.