PHP calculator class: Perform Arithmetic operations

PHP OOP: Exercise-16 with Solution

Write a PHP class called 'Calculator' that has a private property called 'result'. Implement methods to perform basic arithmetic operations like addition and subtraction.

Sample Solution:

PHP Code :

class Calculator {
    private $result;

    public function __construct() {
        $this->result = 0;

    public function getResult() {
        return $this->result;

    public function add($number) {
        $this->result += $number;

    public function subtract($number) {
        $this->result -= $number;

$calculator = new Calculator();


$result = $calculator->getResult();
echo "Result: " . $result;

Sample Output:

Result: 6


In the above exercise -

  • The "Calculator" class has a private property $result, which is initially set to 0 in the constructor method __construct().
  • The getResult() method retrieves the current value of the $result property.
  • The add($number) method takes a number as a parameter and adds it to the current value of $result.
  • The subtract($number) method takes a number as a parameter and subtracts it from the current value of $result.


Flowchart: PHP class for file operations.

PHP Code Editor:

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