Question 169580
 cashier has P 50, P 100, and P500 bills. the number of P50 bills is 5 more than 7 times the number of P100 and the number of P500 bills is four-fifths the number of P100 bills. If the total amounts that she has P18 100, how many of each type of bills are there?
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Let # of P50 be "x":
Let # of P100 be "y":
Let # of P500 be "z":
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EQUATIONS:
x = 7y + 5
z = (4/5)y
50x + 100y + 500z = 18100
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Rearrange:
50x + 100y + 500z = 18100
x   -7y    +  0   =  5
0    + 4y  -  5z  =  0
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Use any method you know to get:
x = 152
y = 21
z = 16 
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Cheers,
Stan H.