Question

The area of the trapezium is $100m^2$ and height is $10m.$ Find the length of one parallel side if the length of the other parallel side is $5m.$

• A. $5m$
• B. $10m$
• C. $15m$
• D. $20m$

Answer 1

The correct option is C $15m$

Consider that $A$ is the area of the trapezium, $a,b$ are the length of the parallel sides, and $h$ is the height of the trapezium.

Given:

$A=100m^2$

$h=10m$

$a=5m$

So,

$\begin{array}{cc}A& =\frac{1}{2}\times \left(a+b\right)\times h\\ 100& =\frac{1}{2}\times \left(5+b\right)\times 10\\ 20& =5+b\\ b& =15m\end{array}$

Hence, option $C$ is correct.