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What is 20 Percent of 31?

20% of 31 = 6.2

Step by step

  1. Turn the percentage into a decimal: 20 ÷ 100 = 0.2
  2. Multiply: 0.2 × 31 = 6.2

How the answer is worked out

“Percent” means “per hundred”, so 20% is 20 out of every 100, or 0.2 as a decimal. Taking 20% of 31 means multiplying 31 by 0.2, which gives 6.2.

6.2 is the 20% share of 31. The remaining 80% is 24.8, and the two parts add back up to 31.

Why calculate this?

Taking a percentage of a number is how discounts, tips, tax and interest are worked out.

  • Discounts: 20% off an item priced $31 saves $6.2, so you pay $24.8.
  • Tips: a 20% tip on a bill of $31 is $6.2, so the total is $37.2.
  • Interest: simple interest of 20% a year on $31 earns $6.2 in one year and $31 over five years.
  • Tax: a sales tax of 20% on a price of $31 adds $6.2, so the price including tax is $37.2.

A quicker way

Use 10% and 1%: 10% of 31 is 3.1 and 1% is 0.31. 20% is 2 × 10% = 6.2 = 6.2.

Swap the numbers if that is easier: 20% of 31 is always the same as 31% of 20, because both are 20 × 31 ÷ 100.

Check the answer

Work backwards: 6.2 ÷ 31 × 100 = 20%. Getting 20% back shows the answer is right.

Rounding

Rounded to a whole number the result is 6, to one decimal place 6.2 and to two decimal places 6.20. Round only at the end: rounding halfway through a calculation can change the last digit.

The formula explained

result = percentage ÷ 100 × number. Dividing the percentage by 100 turns it into a decimal multiplier, so 25% becomes 0.25 and 150% becomes 1.5. Multiplying the number by that decimal gives the share.

Another worked example: 5% of 23

  1. Turn the percentage into a decimal: 5 ÷ 100 = 0.05
  2. Multiply: 0.05 × 23 = 1.15

Common percentages of 31

10% of 31 is 3.1, 20% is 6.2, a quarter (25%) is 7.75, half (50%) is 15.5 and three quarters (75%) is 23.25. Knowing these makes it easy to estimate any other percentage of 31 in your head.

Adding and taking away 20%

Increasing 31 by 20% gives 37.2 and decreasing it by 20% gives 24.8. These do not cancel out: raising 31 by 20% and then lowering the result by 20% ends at 29.76, because the second 20% is taken of a bigger number.

Finding the original number

If 6.2 is 20% of something, divide by 0.2 to get it back: 6.2 ÷ 0.2 = 31. This is how you work out a price before tax or a full amount from a share of it.

Other ways to ask this

The same calculation is often asked in other words. All of these have the answer above:

  • What is 20 percent of 31?
  • 20% of 31
  • 20 percent times 31
  • Find 20% of 31
  • How much is 20 per cent of 31?

Terms used on this page

  • Percentage: the rate, the number with the % sign.
  • Base: the number you take the percentage of.
  • Decimal multiplier: the percentage divided by 100.
  • Mark-up and discount: adding or taking away a percentage of a price.

The answer in other forms

Result6.2
Remaining24.8
20% as decimal0.2
31 + 20%37.2

Related results

5% of 31

5% of 31 = 1.55

10% of 31

10% of 31 = 3.1

15% of 31

15% of 31 = 4.65

25% of 31

25% of 31 = 7.75

50% of 31

50% of 31 = 15.5

75% of 31

75% of 31 = 23.25

The other way round: 31% of 20

Doing it in a spreadsheet

In Excel, Google Sheets or Numbers type =20%*31 into any cell. Replace the numbers with cell references (for example A1 and B1) to reuse the formula for a whole column.

Common mistakes

Forgetting to divide the percentage by 100 makes the answer 100 times too big. Note that x% of y always equals y% of x.

Practice examples

5% of 23
Show answer

5% of 23 = 1.15

81% of 46
Show answer

81% of 46 = 37.26

18% of 60
Show answer

18% of 60 = 10.8

39% of 80
Show answer

39% of 80 = 31.2

50% of 86
Show answer

50% of 86 = 43

46% of 59
Show answer

46% of 59 = 27.14

77% of 51
Show answer

77% of 51 = 39.27

94% of 96
Show answer

94% of 96 = 90.24

37% of 14
Show answer

37% of 14 = 5.18

68% of 78
Show answer

68% of 78 = 53.04

Calculate another

How this answer was calculated

The result is worked out from the numbers in this page's address when the page is opened, using exact arithmetic wherever possible and rounding only for display. Nothing is copied from a printed table. If you think an answer is wrong, please tell us through the contact page and we will check it.

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Questions

What is 20 Percent of 31?

20% of 31 is 6.2. Formula, steps and practice examples.

What is 20% off 31?

24.8. Taking 20% off leaves 80% of 31.

What is 31 plus 20%?

37.2. Adding 20% is the same as multiplying by 1.2.

What is 20% of 31 as a fraction?

20/100 × 31 = 620/100, which simplifies to 31/5.

How do I find 20% of a number on a calculator?

Multiply the number by 0.2. For 31 that is 31 × 0.2 = 6.2. On many calculators you can also type 31 × 20 %.