Question

A plasterer buys fifteen 25kg bags of plaster. At the end of the week, only 10% of the plaster

is left. How much plaster did they use?

Answer 1

The plasterer used 337.5 kg of plaster.

Step-by-step explanation:

To find out how much plaster the plasterer used, we need to subtract the amount of plaster that is left from the total amount of plaster bought. Since only 10% of the plaster is left, the plasterer used 90% of it. To calculate this, we can use the formula: Total plaster used = Total plaster bought x Percentage used

Total plaster used = 15 bags x 25 kg/bag x 90%

Total plaster used = 15 bags x 25 kg/bag x 0.9 = 337.5 kg

Therefore, the plasterer used 337.5 kg of plaster.

Answer 2

The plasterer bought 15 x 25 = 375 kg of plaster.
If only 10% is left, then they used 100-10 = 90% of the plaster.
So they used 375 x 90/100 = 337.5 kg of plaster.