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100 decreased by 10% = 90

100 decreased by 10 percent is 90. Step-by-step solution with the formula and worked example.

100 decreased by 10% = 90
decreased by %

Solution: 100 decreased by 10 percent

Decrease = 10% × 100 = 10
Result = 100 − 10 = 90

Step-by-step explanation

  1. Find the decrease: 10% of 100 = 10.
  2. Subtract it from the original: 100 − 10 = 90.
  3. Shortcut: multiply by (1 − 10/100) = ×0.9.

Good to know

Shortcut: decreasing by 10% is the same as multiplying by 0.9 (that is 100% − 10%). So 100 × 0.9 = 90 in one step.

Frequently asked questions

100 decreased by 10 percent
100 decreased by 10% = 90.

How is it calculated?
See the step-by-step solution above — it uses the standard percentage formula.

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