Question

Find the breadth of a rectangle whose area is \[246sqcm\] and length is \[20cm\]

Answer 1

Hint: The property of rectangle that we need to know is: The opposite sides of rectangle are equal. That is lengths of the rectangle are equal and breadths of the rectangle are equal. Area of a rectangle is given by \[Area = l \times b\],where \[l\] is the length of the rectangle and \[b\] is the breadth of the rectangle.

Complete step-by-step solution:

It is given that the length of a rectangle is \[20cm\] and the area of a rectangle is \[246sqcm\].
That is \[l = 20cm\] and \[Area = 246sqcm\].
Our aim is to find the breadth of a rectangle. Since the formula of area of a rectangle has the components length and breadth, we are using this to get the value of breadth.
We know that the area of a rectangle is, \[l \times b\].
Let us substitute the given values in the formula.
\[Area = l \times b \\
   \Rightarrow 246 = 20 \times b \]
Let us take \[20\] to the other side of the equation.
\[\dfrac{{246}}{{20}} = b\]
We know that when we take a term to the other side of the equation its operation changes. Let us rewrite the above equation for our convenience.
 \[b = \dfrac{{246}}{{20}}\]
Let’s simplify this to get the value of the breadth of a rectangle.
\[b = \dfrac{{123}}{{10}}\]
Let us divide \[123\] by \[10\], we get
\[b = 12.3\]
Thus, the breadth of a rectangle is \[12.3cm\].

Note: We have to wisely choose the formula so that it contains the components that we have and also the component that we have to find. Here area and length of a rectangle are given. We have to find breadth, so we have used the formula of area since it contains the components that we have (i.e., area and length) and also the component that we need (i.e., breadth).