What are the potential pitfalls of using string functions for mathematical operations in PHP?

Using string functions for mathematical operations in PHP can lead to inaccurate results due to potential issues with data type conversion and precision. To ensure accurate mathematical operations, it is recommended to use PHP's built-in math functions or explicitly convert strings to numbers before performing calculations.

// Incorrect way of using string functions for mathematical operations
$num1 = "10";
$num2 = "20";
$result = $num1 + $num2; // This will concatenate the strings instead of adding them

// Correct way of performing mathematical operations
$num1 = "10";
$num2 = "20";
$result = (int)$num1 + (int)$num2; // Explicitly convert strings to integers before addition
echo $result; // Output: 30