## PHP Arithmetic Assignment Operators

PHP provides arithmetic assignment operators which combine arithmetic operations and assignment in a single operation. These operators are useful when you want to update a variable’s value by performing an arithmetic operation on it.

Here are the arithmetic assignment operators in PHP:

1. Addition assignment operator: `+= `

The addition assignment operator adds the value on the right-hand side to the value on the left-hand side and assigns the result to the left-hand side variable.

``````<?php

\$a = 5;
\$b = 3;
\$a += \$b;  // \$a now contains 8

?>``````
1. Subtraction assignment operator: `-=`

The subtraction assignment operator subtracts the value on the right-hand side from the value on the left-hand side and assigns the result to the left-hand side variable.

Example:

``````<?php

\$a = 10;
\$b = 3;
\$a -= \$b;  // \$a now contains 7

?>``````
1. Multiplication assignment operator: `*=`

The multiplication assignment operator multiplies the value on the left-hand side by the value on the right-hand side and assigns the result to the left-hand side variable.

Example:

``````<?php

\$a = 2;
\$b = 5;
\$a *= \$b;  // \$a now contains 10
?>``````
1. Modulus assignment operator: `%=`

The modulus assignment operator calculates the remainder of the division of the left-hand side by the right-hand side and assigns the result to the left-hand side variable.

Example:

``````<?php

\$a = 10;
\$b = 3;
\$a %= \$b;  // \$a now contains 1

?>``````

These arithmetic assignment operators can be combined with any arithmetic operation and are very useful for shortening code and improving readability..

Example for PHP Arithmetic Assignment Operators

``````<?php
\$num = 2;
\$num += 2; // New value is 4
echo "New value is \$num <br />";
\$num -= 1; // New value is 3
echo "New value is \$num <br />";
\$num *= 4; // New value is 12
echo "New value is \$num <br /> ";
\$num /= 2; // New value is 6
echo "New value is \$num <br />";
\$num %= 4; // New value is 2
echo "New value is \$num<br />";
?>``````