The lengths of two parallel sides of a trapezium are in the ratio 9:11 and the 2 perpendicular distance between them is 12 cm. If the area of the trapezium is 480cm ,
then find the sum of length of both the parallel sides.

Step-by-step explanation:

Let the parallel sides be 2x and 3x respectively.

Area of trapezium =420 square cm

Or 1/2×(sum of parallel sides)×(distance between the parallel sides)=420 square cm

Or 1/2×(2x + 3x)×8=420 square cm

Or 1/2 × 5x × 8=420 square cm

Or 20x = 420 square cm

Or x=21 cm

First side =2x =2×21=42 cm

Second side =3x =3×21 =63 cm

Lets furnish the 6th grade maths.

Formula of Area of Trapezium :- (Sum of parallel sides/2)*(perpendicular distance between parallel sides)

Given in the question:-

Parallel sides = 2x and 3x (common factor is assumed as x)

Area = 420

Perpendicular distance = 8

Now put the value in formula.

420 = [(2x + 3x)/2] * 8

5x = 420/4

x = 105/5

x = 21

Hence, parallel sides of trapezium is 42 (2*21) and 63 (3*21).

Correct me if I’m wrong.

Let the parallel sides of the trapezium be AB and CD.

Let AB be 2x and CD = 3x.

The distance between AB and CD = 8 cm.

So the area of ABCD = (AB + CD)*8/2 = 420 or

(2x +3x) = 420/4 = 105, or

5x = 105, or

x = 21.

So AB = 42 cm and CD = 63 cm.

Check: Area of ABCD = (42+63)*8/2 = 105*8/2 = 420 sq cm. Correct.

So the parallel sides of the trapezium are 42 cm and 63 cm.

answer: c i think

step-by-step explanation: