Answer: D) $17.44
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Explanation:
First we need to calculate the percent increase of the popular book
A = old price = 11.75
B = new price = 12.57
C = percent change
C = 100*(B-A)/A
C = 100*(12.57-11.75)/(11.75)
C = 6.9787% approximately
The positive C value indicates a percent increase.
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The less popular book gets roughly a 6.9787% price decrease or discount.
100% - 6.9787% = 93.0213%
The less popular book is now 93.0213% of its original price of $18.75
Apply this percentage to the original price
93.0213% of 18.75 = (93.0213/100)*18.75 = 17.4415 which rounds to 17.44
