Ron found 12 coins. 1/3 are pennies,1/4 of them were nickles, 1/6 of them were dimes and the rest?

I can never remember what the value of a nickel/nickle is and what a dime is. I think 5c and 10c but that doesn't seem important here.

1/3 coins were pennies... so 4 coins.
1/4 were nickles/nickels. 3 coins.
1/6 were dimes. 2 coins.

That makes 9 coins. There are 3 more. As to what they are, we haven't been given enough information to find out. All we know is that there are three other coins.