SOLUTION: The teller has a total of 30 bills 1's, 5's and 20's. The 20's are 9 more than the number of 1's. Total value of the money is $351. How many of each denomination are in the cash dr

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Question 1031350: The teller has a total of 30 bills 1's, 5's and 20's. The 20's are 9 more than the number of 1's. Total value of the money is $351. How many of each denomination are in the cash drawer.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
X-number of ones
Y-number of fives
Z-number of twenties
1.X%2BY%2BZ=30
.
.
Z=9%2BX
2.-X%2BZ=9
.
.
3.X%2B5Y%2B20Z=351
Use Cramer's rule,
A=%28matrix%283%2C3%2C%0D%0A1%2C1%2C1%2C%0D%0A-1%2C0%2C1%2C%0D%0A1%2C5%2C20%29%29
abs%28A%29=11
.
.
A%5BX%5D=%28matrix%283%2C3%2C%0D%0A30%2C1%2C1%2C%0D%0A9%2C0%2C1%2C%0D%0A351%2C5%2C20%29%29
abs%28A%5BX%5D%29=66
.
.
A%5BY%5D=%28matrix%283%2C3%2C%0D%0A1%2C30%2C1%2C%0D%0A-1%2C9%2C1%2C%0D%0A1%2C351%2C20%29%29
abs%28A%5BY%5D%29=99
.
.
A%5BZ%5D=%28matrix%283%2C3%2C%0D%0A1%2C1%2C30%2C%0D%0A-1%2C0%2C9%2C%0D%0A1%2C5%2C351%29%29
abs%28A%5BZ%5D%29=165
.
.
X=abs%28A%5BX%5D%29%2Fabs%28A%29=66%2F11=6
Y=abs%28A%5BY%5D%29%2Fabs%28A%29=99%2F11=9
Z=abs%28A%5BZ%5D%29%2Fabs%28A%29=165%2F11=15