Question

find the area of trapezium whose parallel sides are 20cm and 18cm long, and the distance between them is 15cm.​

Answer 1

Answer :

Given : Two parallel sides of a trapezium measure 20cm and 18 cm . It's height is 15 cm

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To find : Area of the trapezium

Solution :

We know that the formula for finding the area of a trapezium is 1/2 × h ( a + b )

Where , a and b are the two parallel sides and h stands for height .

On substituting the given values in the this formula we get ,

$\sf{\implies\:Area\:of\: trapezium\:=\:\dfrac{1}{2}\:\times\:h(a+b)}$

$\sf{\implies\:Area\:of\: trapezium\:=\:\dfrac{1}{2}\:\times\:15(20+18)}$

$\sf{\implies\:Area\:of\: trapezium\:=\:\dfrac{1}{2}\:\times\:15\:\times\:38}$

$\sf{\implies\:Area\:of\: trapezium\:=\:\dfrac{1}{2}\:\times\:570}$

$\sf{\implies\:Area\:of\: trapezium\:=\:285\:cm^2}$

Calculations step by step :

1. First we got the values of the parallel sides and height of the figure from the Question
2. Then we used the formula $\sf{\implies\:Area\:of\: trapezium\:=\:\dfrac{1}{2}\:\times\:h(a+b)}$
3. Filled the values in the formula
4. Did the calculations
5. Got the area of the desired trapezium

Answer 2

$\LARGE{\underline{\blue{\sf{Solution:-}}}}$

Find the area of trapezium whose parallel sides are 20cm and 18cm long, and the distance between them is 15cm.

GivEn :-

Parallel side a = 20 cm.

Parallel side b = 18 cm.

Distance between them = 15 cm. ( Height )

To finD :-

The area of trapezium.

Steps :-

We have one particular formula to find the area of trapezium, that is, 1 / 2 × h ( a + b )

Here , ' h ' is for height. And a + b is the sum of both Parallel sides of trapezium.

So , Area of trapezium = 1 / 2 × h ( a + b )

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀ ⠀= 1 / 2 × 15 ( 20 + 18 )

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀= 1 / 2 × 15 × 38

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀= 15 × 19

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀= 285 cm²

Therefore, the area of trapezium is equals to 285 cm².

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