Write down 12 bills and 11 coins that add to a total of $106.69?
Analyze the bills and coins separately.
For $.69, you must have 4 pennies, so only seven coins remain to be determined. If the remaining $.05 are also pennies, that leaves only two coins remaining to get $.60. Can't be done. So the $.05 is determined by a nickel. That leaves 6 coins remaining to get $.60.
Use a similar process for the bills.