Answer :
So tommy has 1/3 dimes as nickels so you need to guess and cheak a d then you go to the method they gave you and you get 2 dimes 6 nickels and 9 quarters
Nickels = 6
Dimes = 2
Quarters = 9
(1/3N) + N + (3+N) = 17
2 1/3N = 14
N = 6
Dimes = 2
Quarters = 9
(1/3N) + N + (3+N) = 17
2 1/3N = 14
N = 6