You can put this solution on YOUR website! Let n be the number of nickels and d be the number of dimes that Phil has.
Since each nickel is worth 5 cents, and each dime is worth 10 cents, we have: (1)
(Note: we had to use 415 rather than 4.15 since we are counting in cents)
We also know that (2)
Substituting (2) into (1),
Now substituting this value of d into (2) we get:
So Phil has 17 nickels and 33 dimes.