Question 1028923
A woman bought 100 Christmas cards. For the ones that sing a song when you open them, she paid 30 cents each. For the rest she paid 5 cents each. If the cards cost $10.25 in all, how many of the expensive kind did she buy?
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Equations:
s + r = 100 cards
30s + 5r = 1025 cents
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Modify for elimination::
s + r = 100
6s + r = 205
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Subtract and solve for "s"
5s = 105
s = 21 (# of song cards)
r = 100 -21 = 79 (# of other cards)
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Cheers,
Stan H.