to do order of operations, the mnemonic my school uses is PEMDAS. This means Parentheses, Exponents, Multiply/Divide, and Addition/Subtraction. In your example, you have to simplify the parentheses first. In the parentheses you still have to do PEMDAS. There is an exponent in the parentheses, so you do that first. Keep simplifying the parentheses; 27 - 25. After doing that, the brackets (same as parentheses) say you have to do 4 x 2 (27-25 is 2). The last step in your equation is to do 64 / 8.