4. A cash register contains $10 bills and $20 bills with a total value of $340. If there are 23 bills total, then how many of each does the register contain?

There are total 17bills of $20 dollars and 6 for $10 bills.

We get the answer of $20 bills by dividing 340 and 20 then we get 17 then subtract the value from total bills than you get 6 bills for $10 dollars