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Coal Truck

Age 14 to 16 Short Challenge Level:

The mass of an empty coal truck before it is loaded is 2000 kg.

At the start of a day it is loaded with coal, and theĀ coal makes up 80% of the total mass.

At the first delivery, the driver unloads a quarter of the coal.

Can you express the mass of coal left on the truck, as a percentage of the total mass, after the driver made the first delivery?

This problem is adapted from the World Mathematics Championships
You can find more short problems, arranged by curriculum topic, in our short problems collection.