SOLUTION: Karen brought 10 stamps. Some cost $.32 and some cost $.20. SHe spent $2.84. How many of each did she buy?

Question 700679: Karen brought 10 stamps. Some cost $.32 and some cost $.20. SHe spent $2.84. How many of each did she buy?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Karen bought 10 stamps. Some cost $.32 and some cost $.20. SHe spent $2.84. How many of each did she buy?
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Quantity Eq:::: a + b = 10
Value Eq::::: 32a + 20b = 284 cents
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32a + 32b = 32*10
32a + 20b = 284
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Subtract and solve for "b":
12b = 36
b = 3 (# of 20 cent stanps)
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Solve for "a":
a + b = 10
a + 3 = 10
a = 7 (# of 32 cent stamps)
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Cheers,
Stan H.
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