Question 993965
a customer walks into a post office to purchase stamps. she purchased a total of 47 stamps some of the stamps are 49 cents stamps and some 33 cent stamps how many 49 cents stamps and how many 33 cents stamps did she purchase if the total cost of all the stamps was 20.31 
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Quantity:: t + n = 47 stamps
Value:: : 33t+49n = 2031 cents
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Modify for elimination:
49t + 49n = 49*47
33t + 49n = 2031
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Subtract and solve for "t"::
16t = 272
t = 17 (# of 33 cent stamps purchased)
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Cheers,
Stan H.
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