At the end of one year, they have $104. Next, apply 4% to the previous $104.
4% of $104 is $4.16. Add that to $104, and you get $108.16. Now, continue and you get the following for each year:
Start: $100
Year 1: $104
Year 2: $108.16
Year 3: $112.49
Year 4: $116.99
Year 5: $121.67
Year 6: $126.54
Year 7: $131.60
Year 8: $136.86
Year 9: $142.33
Year 10: $148.02
The answer is 148,02!
This also rounds up to the penny after each 4% application.