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# Coal Truck

**Answer**: 75%

**Using ratio**

At the beginning of the day, the mass of the truck is 80% coal and 20% truck.

Ratio of truck : coal is 1 : 4

At the first delivery, the truck loses $\frac14$ of the coal:

So the ratio of truck : coal is 1 : 3. That is equivalent to 25% : 75%.

So 75% of the truck's mass is coal after the first delivery.

**Finding the total mass of the truck and the load**

$6000$ kg coal

total mass $8000$ kg.

$\dfrac{6000}{8000}=\dfrac34=75\%$ of the total mass is coal.

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Age 14 to 16

ShortChallenge Level

- Problem
- Solutions

At the beginning of the day, the mass of the truck is 80% coal and 20% truck.

Ratio of truck : coal is 1 : 4

At the first delivery, the truck loses $\frac14$ of the coal:

So the ratio of truck : coal is 1 : 3. That is equivalent to 25% : 75%.

So 75% of the truck's mass is coal after the first delivery.

$6000$ kg coal

total mass $8000$ kg.

$\dfrac{6000}{8000}=\dfrac34=75\%$ of the total mass is coal.

You can find more short problems, arranged by curriculum topic, in our short problems collection.