Question

b. How long will a car take to travel a distance of 120 kilometres on a road, where the speed limit of the road is 65 km/h for first 100 kilometres and then the speed limit is
only 30 km for rest of the distance? The top speed of the car is merely 60 km/h.​

Answer 1

Explanation:

total distance = 120 km

scine the top speed of the car is 60 km/h

for the first 100 km its take time = 100/60 h = 5/3 h

for the rest 20 km its take time = 20/30 h = 2/3 h

total time taken by the car = 5/3 + 2/3 h = 7/3 h

$= 2 \frac{1}{3} h = 2 \: h \: \frac{1}{3} \times 60 \: min = 2 \: h \: 20min$