Question

The area of a trapezium is 384 cm2 if its parallel sides are in the ratio 3:5 and the perpendicular distance between them is 12 cm, the smaller of the parallel side is

Answer 1

Given > height of trapezium = 12cm
Let the common multiple be x ; then
the sides will be
a = 3x
b = 5x

Area of trapezium = (1/2)×(sum of parallel sides)×h
384 = (1/2)×(3x+5x)×12
8x = 64
x = 8

The length of the smaller side
= 3x
= 3×8
= 24 cm
___________________

Answer 2

Given:

Area of trapezium=384 square cm

Ratio of parallel sides=$b_1:b_2=3:5$

Distance between parallel sides=h=12 cm

To find:

Smaller of the parallel sides

Solution:

Let $b_1=3x,b_2=5x$

Area of trapezium=$\frac{1}{2}(b_1+b_2)\times h$

Using the formula

$384=\frac{1}{2}(3x+5x)\times 12$

$384=6(8x)$

$x=\frac{384}{6\times 8}=8 cm$

Substitute the value of x

Smaller side=$b_1=3\times 8=24 cm$

Hence, smaller of the parallel side=24 cm