Here are two slightly different ways to look at it.
Both ways do exactly the same thing.
Way #1:
Divide (the new number) by (the old number)
349 / 320 = 1.090625
Change the quotient 1.090625 to percent.
To change any number into percent, multiply it by 100, or move the decimal point 2 places to the right.
1.090625 ==> 109.06 %
The new number (349) is 109.06% of the old number (320).
But the old number was 100% of itself. So the new number
is 9.06% more than the old number was.
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Way #2:
How much bigger is the new number ?
(349 - 320) = 29 bigger
Divide the increase by the old number:
29 / 320 = 0.090625
Change the quotient to a percent.
0.090625 = 9.06%
The increase is 9.06% of the old number.
