PHP Numbers
Review
Great job! In this lesson, we learned all about using numbers in PHP. Let’s review what we covered:
 PHP has two number data types: integers and floating point numbers
 We can use arithmetic operators for performing math operations:
Operation: 

Example: 
Addition 
+ 
echo 1 + 4.5; // Prints: 5.5 
Subtraction 
 
echo 9  1; // Prints: 8 
Multiplication 
* 
echo 1.9 * 2.9; // Prints: 5.51 
Division 
/ 
echo 9 / 1; // Prints: 9 
Modulo 
% 
echo 11 % 3; // Prints: 2 
Exponentiation 
** 
echo 8**2; // Prints: 64 
 Operations have an order of precedence meaning that certain types of operations in a chain will be evaluated before others: first evaluated will be any operation wrapped in parenthesis (
()
), next exponents (**
), then multiplication (*
) and division (/
), and finally addition (+
) and subtraction (
). The acronym PEMDAS can be a helpful way of remembering the order.
 We can assign number values to variables and then perform numerical operations with them.
 We can use mathematical assignment operators as a shorthand when reassigning number variables:
Operation: 
Long Syntax: 
Short Syntax: 
Add 
$x = $x + $y 
$x += $y 
Subtract 
$x = $x  $y 
$x = $y 
Multiply 
$x = $x * $y 
$x *= $y 
Divide 
$x = $x / $y 
$x /= $y 
Mod 
$x = $x % $y 
$x %= $y 