Question

The cross-section of a cannel is a trapezium in shape. If the canal is 15 m wide at the top and 5 m wide at the bottom and the area of cross-section is 560 sq m, the depth of canal is:

• A. 14 m
• B. 28 m
• C. 56 m
• D. 112 m

Answer 1

The correct option is C 56 m

Area of a trapezium $=\frac{1}{2}\times$ (sum of parallel sides) $\times$ distance between them
$560=\frac{1}{2}\times (15+5)\times depth$
depth $=56m$