Order of Operations is about which number operation to do first. The acronym PEMDAS is helpful in reminding us (PEMDAS stands for Parentheses, Exponent, Multiply, Divide, Add, Subtract. Exponents are often called 'powers' such as "3 squared" 3² = 3x3 or 5 to the power of 3, 5³ = 5x5x5=125. For PEMDAS rules, Exponent can mean any 'self operation' on a number including "square root" and fractions as in ¾. So ¾ of 20 - 8 = (20 ÷ 4 x 3) - 8 = 15 - 8 = 7
The order is not always that which is presented. We often use parentheses to 'force' the first operation. Sometimes we don't need the parentheses eg. sums A and B don't need brackets because you multiply before you add but without the brackets in 4 + 3 x 5, many people would add first and give the wrong answer 35 (when it should be 19). Brackets (parentheses) are essential in sums C and D, to force the Addition operation before Multiplication. So too the brackets are essential in situation E to force the Subtraction before the Multiplication.
