You follow the rule PEMDAS parenthesis, exponent, multipy, divide, add, substart. So you would start off by doing 27-12x2, you would do 12x2=24 first then 27-24=3. So then it would be 4+3/2, do 3/2=1.5, then add it 4+1.5=5.5. So the correct answer is 5.5
