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?

geometry 
PsyDAG,
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. 
algebra 
PsyDAG,
How does your problem relate to geometry?