Question

The shape of the cross section of a canal is a trapezium. If the canal is 10 m wide at the top, 6 m wide at the bottom and the area of its cross section is 640m², find the depth of the canal.

Answer 1

Area of the canal = 640m²

Area of trapezium = \(\frac{1}{2}\) x (Sum of parallel sides) x (Distance between them)

\(\Rightarrow 640=\frac{1}{2}\times (10+6)\times h\)

\(\Rightarrow\) \(\frac{1280}{16}=h\)

\(\Rightarrow\) h = 80 m

Therefore, the depth of the canal is 80 m.