Answer: Choice B) 122%
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Work Shown:
A = 1250 is the initial amount
B = 2780 is the new amount
C = percent change = unknown for now
The formula to use is
C = [ (B-A)/A ] * 100
to calculate the percent change.
Basically we calculate the change (B-A) first and then divide that over the original amount A to compute the decimal form of the answer, which is then converted over to percentage form. The "100" tacked on at the end is what converts from decimal to percent form.
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C = [ (B-A)/A ] * 100
C = [ (2780 - 1250)/1250 ] * 100
C = (1530/1250)*100
C = 1.224 * 100
C = 122.4%
C = 122%
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The positive C value indicates we have a percent increase. If C were negative, then we'd have a percent decrease.