Problema Solution
A car travelled on a B class road for 20 minutes at an average speed of 57
km/h. It then travelled a distance of 55 km in 30 minutes on an expressway.
Find
(a) the distance the car travelled on the B class road;
(b) the average speed, in km/h, of the car when it travelled on the expressway.
Answer provided by our tutors
(a) the distance the car traveled on the B class road
Since
Distance = Average Speed * Time
we have
Distance = 57*(20/60) since 20 min = 20/60 hours
Distance = 19 km
The car traveled 19 km on the B class road.
(b) the average speed, in km/h, of the car when it traveled on the expressway.
Since
Average Speed = Distance/Time
we have
Average Speed = 55/(30/60) since 30 min = 30/60 hours
Average Speed = 110 km/h
The average speed of the car when it traveled on the expressway was 110 km/h.