Answer:
43 paperback books
Explanation:
7.50(15) + 1.25x = 166.25
112.50 + 1.25x = 166.25
Subtract 112.50 from both sides
(112.50 - 112.50) + 1.25x = (166.25 - 112.50)
1.25x = 53.75
Divide 1.25 from both sides
x = 43
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