SOLUTION: Juana bought 16 used paperback books for $10.95. Some cost $.60 and the rest cost $.75 each. How many of each did she buy?

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Question 603942: Juana bought 16 used paperback books for $10.95. Some cost $.60 and the rest cost $.75 each. How many of each did she buy?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Juana bought 16 used paperback books for $10.95. Some cost $.60 and the rest cost $.75 each. How many of each did she buy?
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Equations:
a + b = 16
0.6a + 0.75b = 10.95
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a + b = 16
60a + 75b = 1095
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a = 16-b
12a + 15b = 219
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Substitute for "a" and solve for "b":
12(16-b) + 15b = 219
192 - 12b + 15b = 219
3b = 27
b = 9 (# of 0.60 books)
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a = 16-9 = 7 (# of 0.75 books)
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Cheers,
Stan H.
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