Question

At noon, a tank contained 10 cm of water. After several hours, it contained 7 cm of water. What is the percent decrease of water in the tank?

Please answer with explanation.

Answer 1

The tank decreased from 10 cm to 7 cm, so the tank lost 3 cm of water.
So 30%.was lost

Answer 2

Answer:

10cm - 7cm = 3cm

this 3cm is the decrease in the depth of water, let us find the percentage decrease.

%decrease=(decrease÷original depth) × 100%

%decreas=(3cm÷10cm)×100%

therefore we get 30%