Mathematics for IGCSE & O level - The Four Operations (Section 1 - No. 39)

Which of the following calculations demonstrate the correct order of operations?

5 + 2 x 3 = 7 x 3 = 21

5 + 2 x 3 = 5 + 6 = 11

(5 + 2) x 3 = 7 x 3 = 21

(5 + 2) x 3 = 5 + 6 = 11

Multiplication is handled before addition in the first case. Brackets are used correctly in the third.