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Upper primary school mathematics question UPQ146
The distance between JB Central and Simei was 520 km. At 8.30 a.m., a van left JB Central for Simei travelling at a constant speed. At the same time, Sarin’s father drove a car travelling at a constant speed set off from Simei towards JB Central. The two vehicles met each other at 12.30 p.m. The car was travelling at 20 km/h faster than the van. What was the speed of the car that drive by Sarin’s father?
The van and the car start at 8.30 a.m and met at 12.30 p.m
Time required to travel the distance = 4 hours
The relative speed between the car and van = 520 ÷ 4 = 130km/h
As both travelled in opposite direction, we can have the below model based on speed
2U + 20 = 130
1U = 110 ÷ 2 = 55km/h
The speed of the car = 55 + 20 = 75km/h