geometry
posted by bilal on .
a bank teller has a total of 124 bills in fives and tens. the total value of the money is $840. how many of each kind does he have?

Let x = $5 bills and y = $10 bills
x + y = 124
x = 124y
5x + 10y = 840
Substitute 124y for x in third equation and solve for y. Insert that value into the first equation and solve for x. Check by inserting both values into the last equation. 
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