First is G, so I take care of groupings first. (2 + 1) is in parentheses, so evaluate that first. 2 + 1 = 3, so I can rewrite the expression as 3+6÷2×3-5. Next is M, so take care of the multiplication and division as they occur from left to right. First is 6÷2 = 3, so the expression becomes 3+3×3-5. Next, 3 × 3 = 9, so the expression is now 3+9-5. Since only S, or subtraction and addition, is left, I can work out the rest from left to right. 3+9-5=12-5=7.