Question

The area of a trapezoid varies jointly with the height of the trapezoid and the sum of its two bases. The area of one trapezoid is 150 square centimeters when its height is 12 centimeters and its base sum is 25 centimeters. What is the area of a trapezoid having a height of 20 centimeters and a base sum of 35 centimeters?

Answer 1

Area = 35*20/2 = 35*10 = 350 square centimeters 

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