100 decreased by 80% = 20
100 decreased by 80 percent is 20. Step-by-step solution with the formula and worked example.
100 decreased by 80% = 20
decreased by %
Solution: 100 decreased by 80 percent
Decrease = 80% × 100 = 80
Result = 100 − 80 = 20
Result = 100 − 80 = 20
Step-by-step explanation
- Find the decrease: 80% of 100 = 80.
- Subtract it from the original: 100 − 80 = 20.
- Shortcut: multiply by (1 − 80/100) = ×0.2.
Good to know
Shortcut: decreasing by 80% is the same as multiplying by 0.2 (that is 100% − 80%). So 100 × 0.2 = 20 in one step.
Frequently asked questions
100 decreased by 80 percent
100 decreased by 80% = 20.
How is it calculated?
See the step-by-step solution above — it uses the standard percentage formula.
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