Posted by Doris on .
A manager has $1170 made up of twenties and fifties. The total is 36 bills. How many fiftydollar bills does the manager have?

Algebra 
Doris,
Please show me how to set this problem up. I am confused.

Algebra 
Alex,
You need to set up a system of equations. No one knows how many of each type of bill there is. Let t=twenties and f=fifties.
t+f=36
20t+50f=1170
20(t+f=36)=20t+20f=720
20t+50f=1170
30f=450 f=15
t+15=36
15 15
t=21