Answer: C) 25%
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Work Shown:
A = old value = 400
B = new value = 300
C = percent change
C = [(B-A)/A]*100%
C = [(300-400)/400]*100%
C = (-100/400)*100%
C = (-0.25)*100%
C = -25%
The negative value of C means we have a percent decrease. Specifically we have a 25% decrease.
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We can see that by saying:
25% of 400 = 0.25*400 = 100
400 - (25% of 400) = 400 - 100 = 300
