Dam

Geometry Level 2

The cross section of a dam is shown above. The volume of the dam is $184500\text{ m}^3$ .

How long is the dam (in meters)?

1 solution

A Former Brilliant Member
Oct 29, 2016

In attacking problems like this, we need to divide the dam into parts (areas). One way is to form rectangles, triangles , etc.

$V$ $=$ $area$ $of$ $section$ $*$ $L$

$area$ $of$ $cross$ $section$ $=$ $A1$ $+$ $A2$ $=$ $\frac{1}{2}$ $(10 + 48)$ $55$ $+$ $(5)(50)$ $=$ $1845$ $m^2$

$184500$ $=$ $1845$ $*$ $L$

$L$ $=$ $100$ $m$