Question

The cross section of a canal is trapezium. If width of the upper side is $10$m and that of base is $6$m and cross section area of the canal is $72$ $m^2$, find its depth.

Answer 1

Let depth $=h$

cross section area $=72$

$\frac{1}{2}h(10+6)=72$

$\frac{h}{2}\times 16=72$

$h\times 8=72$

$h=9$

$\therefore depth=9m$