The area of a trapezium is 405 cm2. Its parallel sides are in the ration 4:5 and the distance between them is 18 cm. Find the length of each of the parallel sides.
Given
Lengths of the parallel sides are in the ratio 4:5
Therefore let one of the side length be 4X and other side length be 5X
Area of trapezium= 405 cm2
Let Height (h) =18 cm
We know that area of trapezium is 
× (sum of parallel sides) × height
Therefore Area of trapezium is 
x (4X +5X) × 18 =405 cm2.
× (4X + 5X) × 18 =405
⇒(9X) × 9 =405
⇒ 81X = 405
⇒ X =
= 5
... Length of the parallel sides is 4X=4 × 5 =20 cm and 5X = 5 × 5 = 25 cm.
Therefore lengths of the parallel sides are 20 cm, 25 cm.
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