Question

A cylindrical well is 15 meters deep and has a diameter of 1.6 meters. Approximately how many cubic meters of soil were dug out to make the well? (Use π = 3.14.) 30.14 cubic meters 37.68 cubic meters 120.57 cubic meters 188.40 cubic meters?

Answer 1

We can dig out the soil from the well equal to volume of well.

Height(h) of well is = 15 meters.

Diameter = 1.6 meters.

So radius(r) = $\frac{1.6}{2} = 0.8$ meter.

As well in cylindrical shapes.

So volume of well = $\pi r^2h$
                               = $\pi * (0.8)^2 * 15$
                                $= 9.6 * \pi$
 In general $\pi = 3.14$

So volume of well is = $9.6 * 3.14$
                                   $= 30.144$ cubic meter.

So we can dig out 30.144 cubic meter soil from well.