Sumwise

Percentage Difference between 30 and 90

Between 30 and 90: 100% difference

Difference
100%
Gap
60
Average
60
Ratio
3 : 1

Sumwise · Maintained by Theo Abbott (pen name) · automated checks · Data: exact arithmetic; unit definitions from NIST SP 811 · Updated · How the checks work

How to work it out

  1. Gap between the values: |30 − 90| = 60
  2. Average of the values: (30 + 90) ÷ 2 = 60
  3. Divide the gap by the average and multiply by 100: 60 ÷ 60 × 100 = 100%
  4. Check: Work backwards: 1 × 60 = 60, the gap between the values.

In a spreadsheet: =ABS(30-90)/((30+90)/2)*100. Dividing by one of the values instead of their average turns it into a percentage change, which depends on which value you start from.

What the result means

90 is 60 more than 30. Measured against their average, 60, that gap is 100%. The result is the same whichever value you name first.

Prices: if one shop charges $30 and another $90 for the same item, the prices differ by 100%.

Why the average is the base

Dividing the gap of 60 by 30 gives 200%, and dividing it by 90 gives 66.6667%. The average, 60, sits between them, so the result does not depend on which value is listed first.

Related results

Results for nearby numbers
30 and 100

Between 30 and 100: 107.6923% difference

30 and 80

Between 30 and 80: 90.9091% difference

40 and 90

Between 40 and 90: 76.9231% difference

20 and 90

Between 20 and 90: 127.2727% difference

The other way round: Percentage change from 30 to 90. Percentage difference is symmetric: between 90 and 30 it is the same 100%, so there is one page for each pair of numbers. Percentage change is not: from 30 to 90 is +200%, from 90 to 30 is -66.6667%.

Practice

7 and 93
Show answer

Between 7 and 93: 172% difference

55 and 66
Show answer

Between 55 and 66: 18.1818% difference

15 and 18
Show answer

Between 15 and 18: 18.1818% difference

50 and 54
Show answer

Between 50 and 54: 7.6923% difference

33 and 84
Show answer

Between 33 and 84: 87.1795% difference

66 and 88
Show answer

Between 66 and 88: 28.5714% difference

Calculate another

How answers are calculated and checked: methodology.

Questions

Percentage Difference between 30 and 90

The percentage difference between 30 and 90 is 100%: the gap divided by the average. Formula and steps.

What is the percentage change from 30 to 90?

+200%. Percentage change uses the starting value (30) as the base, so it is larger than the percentage difference of 100%.

What is the difference between percentage difference and percentage change?

Percentage change compares a new value with an old one and divides by the old value. Percentage difference compares two values on an equal footing and divides by their average, so the order does not matter.