Question

10 – 4 ÷ (-2) + (9 – 5) ● 3

He worked the problem from left to right and got an answer of 3. His teacher marked the problem incorrect. Why is William’s answer incorrect? Show and explain what William did incorrectly. Then, solve the problem correctly and explain how you got the correct answer.

Answer 1

Why not do the problem correctly first? You must follow PEMDAS (order of operations rules). In particular, you must multiply and divide before you add or subtract.

Answer 2

parenthesis comes first, then exponents, then multiply and divide, then add and subtract

Answer 3

There's one set of parentheses, so do the work inside those parentheses first. Show your result, please.