Sumwise

Percentage Change from 30 to 42

From 30 to 42 is a 40% increase

Change
40%
Difference
12
New ÷ old
1.4
Direction
increase

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. Difference: 42 − 30 = 12
  2. Divide by the starting value: 12 ÷ 30 = 0.4
  3. Multiply by 100: 40%
  4. Check: Work forwards from the start: 30 × (1 + 0.4) = 30 × 1.4 = 42.

In a spreadsheet: =(42-30)/30*100. Always divide by the starting value, not the new one. A rise from 40 to 50 is +25%, but the fall from 50 back to 40 is −20%.

What the result means

The new value is 1.4 times the old one: for every 100 at the start there are now 140.

Prices: an item whose price rises from $30 to $42 has gone up by 40%.

Why the change back is different

A 40% rise followed by a 40% fall does not bring you back to 30: it gives 25.2. The second percentage is taken of 42, not of 30, so to undo this change you need 28.5714% instead.

Related results

Results for nearby numbers
30 to 40

From 30 to 40 is a 33.3333% increase

30 to 41

From 30 to 41 is a 36.6667% increase

30 to 43

From 30 to 43 is a 43.3333% increase

30 to 44

From 30 to 44 is a 46.6667% increase

30 to 52

From 30 to 52 is a 73.3333% increase

The other way round: Percentage change from 42 to 30. Percentage change is not symmetric: from 30 to 42 is 40%, but from 42 back to 30 is -28.5714%, because the starting value is the base. For a comparison that is the same both ways, use the percentage difference between 30 and 42: 33.3333%. See Percentage difference between 30 and 42.

Practice

6 to 19
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From 6 to 19 is a 216.6667% increase

83 to 56
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From 83 to 56 is a 32.5301% decrease

50 to 46
Show answer

From 50 to 46 is a 8% decrease

71 to 37
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From 71 to 37 is a 47.8873% decrease

30 to 31
Show answer

From 30 to 31 is a 3.3333% increase

37 to 93
Show answer

From 37 to 93 is a 151.3514% increase

Calculate another

How answers are calculated and checked: methodology.

Questions

Percentage Change from 30 to 42

Going from 30 to 42 is a 40% increase. Formula and steps.

Is going from 30 to 42 an increase or a decrease?

An increase: the value grew by 12, which is 40% of the starting value.

What is the percentage change from 42 back to 30?

-28.5714%. It is a different number because the starting value is now 42, not 30.