SOLUTION: Saul has a combination of $1, $5, and $10 bills in his wallet worth a total of $75. He has a total of 20 bills, and the sum of the number of $5 and $10 bills is the same as the num

Algebra ->  Matrices-and-determiminant -> SOLUTION: Saul has a combination of $1, $5, and $10 bills in his wallet worth a total of $75. He has a total of 20 bills, and the sum of the number of $5 and $10 bills is the same as the num      Log On


   



Question 1019185: Saul has a combination of $1, $5, and $10 bills in his wallet worth a total of $75. He has a total of 20 bills, and the sum of the number of $5 and $10 bills is the same as the number of $1 bills. How many $10 bills does Saul have?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
x=$1
y=$5
z=$10
x+y+z=20
y+z=x
x+5y+10z=75
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substitute second into first
2y+2z=20
y+z=10, after dividing by 2
y+z+5y+10z=75
6y+11z+75
but y=10-z
so 60-6z+11z=75
5z=15
z=3
y=7
x=10
10--$1==$10
7--$5---$35
3--$10--$30