A cashier has a total of 128 ​bills, made up of fives and tens. The total value of the money is $ 890. How many​ ten-dollar bills does the cashier​ have?

Question

I do not know how to set up an equation to solve this

Answer 1

Here's your equations:

 

x + y = 128

 

5x + 10y = 890

 

Use substitution to solve.  You can do it...