25 cents
....25 cents just like any other post-1965 non-proof quarter. State quarters are not rare or valuable unless they are proof or have some error.
It depends on what state it was issued for, post new question
If you mean a 2005s proof California state quarter retail is $1.10
Unless the quarter is in mint-state or a proof, the value would be the melt value of the silver in the coin which is $3.80ish as of this time of writing, but changes depending on the spot price of silver.
A 1999-S Delaware Silver Proof Quarter, certified as a PR-70 Deep Cameo example has a listed retail value of $3,000.00.
1974 S (Proof) Quarter is worth $1.50.
Unless it's Proof, it's just a quarter.
Averge retail value is $2.00 for this coin.
If you found it in change, it's 25 cents. The retail value of a single proof is about a dollar.
A 1988 Proof Quarter is only work the face value, for the most part. To some collectors, they might be willing to pay as much as $18, but this is rare.
There aren't 112 proof state quarters. There are only 50 proof state quarters, (along with 6 in the DC/US territories). Unless you are meaning you had both the clad (copper-nickel, common) proofs and the silver proof sets. But just about every clad US proof state quarter is worth about $1 or so, silver proof quarters go for about $7-8 or about fifty cents or a dollar above melt value individually.
Retail price for a Deep Cameo Proof is $2.30