A swimming pool was 4 meters wide with surface area of 16 square meters. What is the length of the pool?

Answer: 64

Because we're treating the swimming pool as a standard rectangle, rather than a three dimensional shape, we can use the formula L * W = A to calculate the length of the pool.

Length * Width = Area

We've established two key bits of information, and with them we can solve for the final piece.

Length * 4 = 16

4l = 16

Divide both sides by 4.

l = 4

The length of the pool is 4 meters.