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 640 m2, find the depth of the canal.

Given:


Top width = 10 m


Bottom width = 6 m


Area of cross section = 640 m2


Let the depth be h



Now,


Area of trapezium = 1/2 × Sum of parallel sides × Distance between them


640 = 1/2 × (10 + 6) × h


640 × 2 = 16 h



h = 80 m


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