Answer: 25% decrease
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Work Shown:
A = old value = 3000
B = new value = 2250
C = percent change
C = [ (B-A)/A ] * 100%
C = [ (2250-3000)/3000 ] * 100%
C = (-750/3000) * 100%
C = -0.25*100%
C = -25%
Since C is negative, we have a 25% percent decrease.
Another indication we have a percent decrease is that B < A.