What is 100 decreased by 20%?
80
100 decreased by 20% is 80.
How it is worked out
Multiply by 1 minus the percentage as a decimal.
100 × 0.8 = 80 — a reduction of 20
Try your own numbers
Answer80
Open the full percentage calculator for every other form.
Similar percentage questions
- What is 100 decreased by 15% = 85
- What is 100 decreased by 25% = 75
- What is 100 decreased by 10% = 90
- What is 100 decreased by 30% = 70
- What is 100 decreased by 5% = 95
- What is 100 decreased by 40% = 60
Percentage decrease
Questions
- What is 100 decreased by 20%?
- 100 decreased by 20% is 80. 100 × 0.8 = 80 — a reduction of 20.
- How do you work this out?
- Multiply by 1 minus the percentage as a decimal.
- Can I use other numbers?
- Yes — the calculator on this page takes any two numbers, and the full percentage calculator covers every form: percentage of a number, one number as a percentage of another, percentage change, increase and decrease.