Question

The cross-section of a canal is in the form of a trapezium. If the top of canal is 15
wide, the bottom is 8 m and the area of cross-section is 138 m2, find its depth.​

Answer 1

Answer:

12m

Step-by-step explanation:

The cross-section of the canal forms a trapezium in which the sides of 15m and 8m are parallel.

Here,

a=15m

b=8m

h=?   (height;in this case depth)

Area of trapezium = $\frac{h}{2}(a+b)$

$138 = \frac{h}{2}(15+8)\\\\276=23h$

$h= \frac{276}{23}$

∴h=12m

So, the depth is 12m