Percent
Per cent means hundredths. Choose what you want to calculate and see how the answer is found — so you can do it yourself next time.
Your numbers
Answer
20 % of 250
50
How to work it out
- 11 % = 250 / 100 = 2.5
- 220 % = 2.5 · 20 = 50
The formula
del = p/100 · helhed
Per cent means «hundredths»: 20 % = 20/100 = 0.20.
p = del / helhed · 100
ændring % = (efter − før) / før · 100
Always divide by the number BEFORE the change.
ny = gammel · (1 ± p/100)
The growth factor: +20 % is · 1.20, and −20 % is · 0.80.
More: Numbers and percentages
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- Order of operationsEnter a calculation and see it worked out step by step in the right order.
- Number systems and Roman numeralsBinary, hexadecimal and Roman numerals — converted both ways with working.