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Example

Simplifying −30÷2+(−3)(−7)-30 \div 2 + (-3)(-7)

When an expression mixes division, multiplication, and addition without grouping symbols, the order of operations requires completing all multiplications and divisions (from left to right) before any additions:

  1. Divide first (left to right): Because division appears to the left of the multiplication, compute −30÷2=−15-30 \div 2 = -15 first. The expression becomes −15+(−3)(−7)-15 + (-3)(-7).
  2. Multiply: Compute (−3)(−7)=21(-3)(-7) = 21 (same signs produce a positive product). The expression becomes −15+21-15 + 21.
  3. Add: Compute −15+21=6-15 + 21 = 6 (different signs — subtract the smaller absolute value from the larger and take the sign of the number with the larger absolute value).

The final result is 66. This example highlights that multiplication and division share equal priority, so when both appear in an expression they are performed left to right — not multiplication before division. Here the division −30÷2-30 \div 2 is evaluated first simply because it appears further to the left.

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Updated 2026-05-01

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