# Find the percentage change in the area of a Rectangle

Given two integers **P** and **Q** which represents the percentage change in the **length and breadth of the rectangle**, the task is to print the percentage change in the area of the rectangle.

**Examples:**

Input:P = 10, Q = 20Output:32Explanation:

Let the initial length of the rectangle be 100 and breadth be 80.

Initial area = 8000.

New length = 110 and new breadth = 96. Therefore, the new area = 10560.

The percentage change in the area = ((10560 – 8000) / 8000) * 100 = 32.

Input:P = 20, Q = -10Output:8

Let initial length of the rectangle be 100 and breadth be 80.

Initial area = 8000.

New length = 120 and new breadth = 72. Therefore, new area = 8640.

The percentage change in the area = ((8640 – 8000) / 8000) * 100 = 8.

**Approach:**

- Since the area of the rectangle is given by the formula:
area = length * breadth

- Let the initial length of the rectangle be
**L**and the breadth of the rectangle be**B**. Therefore, the initial area is given by**L * B**. - Therefore, the new length and breadth are given as:
L' = L + ((P/100)*L) B' = B + ((Q/100)*B)

- Therefore, the new length and breadth are given as:
**new area = [L + ((C/100)*L)] * [B + ( ( D / 100) * B)]** - The percentage change in the area is given by the formula:

% change = ((new area – old area) / old area )*100Below is the implementation of the above approach:

## C++

`// CPP implementation to find the percentage`

`#include <bits/stdc++.h>`

`using`

`namespace`

`std;`

`// change in the area when the percentage change`

`// in the length and breadth is given`

`// Function to calculate percentage`

`// change in area of rectangle`

`int`

`calculate_change(`

`int`

`length,`

`int`

`breadth){`

`int`

`change = 0;`

`change = length + breadth+((length * breadth)/100);`

`return`

`change;`

`}`

`// Driver code`

`int`

`main()`

`{`

`int`

`cL = 20;`

`int`

`cB = -10;`

`int`

`cA = calculate_change(cL, cB);`

`printf`

`(`

`"%d"`

`,cA);`

`return`

`0;`

`}`

## Java

`// Java implementation to find the percentage`

`import`

`java.util.*;`

`class`

`GFG{`

`// change in the area when the percentage change`

`// in the length and breadth is given`

`// Function to calculate percentage`

`// change in area of rectangle`

`static`

`int`

`calculate_change(`

`int`

`length,`

`int`

`breadth){`

`int`

`change =`

`0`

`;`

`change = length + breadth+((length * breadth)/`

`100`

`);`

`return`

`change;`

`}`

`// Driver code`

`public`

`static`

`void`

`main(String args[])`

`{`

`int`

`cL =`

`20`

`;`

`int`

`cB = -`

`10`

`;`

`int`

`cA = calculate_change(cL, cB);`

`System.out.println(+ cA);`

`}`

`}`

`// This code is contributed by AbhiThakur`

## Python3

`# Python3 implementation to find the percentage`

`# change in the area when the percentage change`

`# in the length and breadth is given`

`# Function to calculate percentage`

`# change in area of rectangle`

`def`

`calculate_change(length, breadth):`

`change`

`=`

`0`

`change`

`=`

`length`

`+`

`breadth`

`+`

`((length`

`*`

`breadth)`

`/`

`/`

`100`

`)`

`return`

`change`

`# Driver code`

`if`

`__name__`

`=`

`=`

`"__main__"`

`:`

`cL`

`=`

`20`

`cB`

`=`

`-`

`10`

`cA`

`=`

`calculate_change(cL, cB)`

`print`

`(cA)`

`# This code is contributed by mohit kumar 29`

## C#

`// C# implementation to find the percentage`

`using`

`System;`

`using`

`System.Collections.Generic;`

`using`

`System.Linq;`

`class`

`GFG`

`{`

`// change in the area when the percentage change`

`// in the length and breadth is given`

`// Function to calculate percentage`

`// change in area of rectangle`

`static`

`int`

`calculate_change(`

`int`

`length,`

`int`

`breadth){`

`int`

`change = 0;`

`change = length + breadth + ((length * breadth)/100);`

`return`

`change;`

`}`

`// Driver Code`

`public`

`static`

`void`

`Main(String[] args)`

`{`

`int`

`cL = 20;`

`int`

`cB = -10;`

`int`

`cA = calculate_change(cL, cB);`

`Console.Write(cA);`

`}`

`}`

`// This code is contributed by shivanisinghss2110`

**Output:**8

**Time Complexity:**O(1)Attention reader! Don’t stop learning now. Participate in the

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