Question

A swimming pool had 2.5 million liters of water in it. Some water evaporated, and then the pool only had 2 million liters of water in it.
What percent of the water evaporated?

Answer 1

Original volume = 2.5 million liters.
After evaporation, the remaining volume is 2 million liters, therefore
Evaporated volume = 2.5 - 2 = 0.5 million liters.

Percent of water evaporated = 100*(0.5/2.5) = 20%

Answer: 20%