nd the area of trapezium whose parallel sides are 20 cm and 16 cm long , and the distance between them is 15 cm ?
"area of a trapezium = 1 / 2 ( sum of parallel sides ) * ( perpendicular distance between them ) = 1 / 2 ( 20 + 16 ) * ( 15 ) = 270 cm 2 answer : a"
divide(multiply(15, add(20, 16)), const_2)