Coal truck

What percentage of the truck's final mass is coal?
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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