Pre-Algebra · Order of operations

Order of Operations with Nested Parentheses

Problem

2+3×(4+5)−6÷22 + 3 \times (4 + 5) - 6 \div 2

Answer

2626

The parentheses act like a box: solve what is inside first, then treat the box as one number.

Step-by-step solution

  1. Work inside the parentheses first.

    4+5=94 + 5 = 9

    Why: Parentheses come before every other operation.

  2. Replace the parentheses with 9.

    2+3×9−6÷22 + 3 \times 9 - 6 \div 2

    Why: The group is now a single number.

  3. Multiply and divide from left to right.

    2+27−32 + 27 - 3

    Why: Multiplication and division rank the same.

  4. Add and subtract from left to right.

    2+27−3=29−3=262 + 27 - 3 = 29 - 3 = 26

    Why: Addition and subtraction rank the same, so work left to right.

Common mistakes

  • Adding 2 + 3 before handling the parentheses.
  • Doing 6 / 2 before 3 x 9. Work left to right.
  • Multiplying 3 x 4 but forgetting the + 5 inside the brackets.

Practice problems

Use the same method. Work each problem on paper, then open the answer to check.

  1. 3+2×(5+1)3 + 2 \times (5 + 1)

    Show answer

    1515

  2. (9−4)×2+3(9 - 4) \times 2 + 3

    Show answer

    1313

  3. 20−2×(6−2)20 - 2 \times (6 - 2)

    Show answer

    1212

  4. 5+2×(10−7)5 + 2 \times (10 - 7)

    Show answer

    1111

  5. (6+2)×3−4(6 + 2) \times 3 - 4

    Show answer

    2020