What amounts of money greater than 10 cents can be formed using dimes and quarters? Use mathematical induction to prove the answer.

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When im thinking of this logically, i know that the minimum amount is 20,25,30,35, 40... and etc. That part is easy, the hard part im having is the first part which is setting this thing up.

1. $\displaystyle P(n): 25a+b> 10 $ // with a >=20? // If all else fails i really need help on the basis case as this will be important for getting the inductive step correct.

2. P(20):

3. Assume:

4. Prove P(n+1)