Google sheets and thickness of wooden board

I'm trying to format a Google sheet to calculate the amount of raw wood I need to buy for a given project.

Raw wood is sold in quarters, for example, 4/4 is a one-inch board, 5/4 is an inch and a quarter, and so on.

I managed to format my cell to always generate a number greater than 4, so if I enter 1 1/8 it will give me 5/4. but the problem with which I find is that there are certain sizes in which wood is not sold, like 7/4 or 9/4, for example.

Is it possible to force a cell to round to a given list of numbers?
4/4, 5/4, 6/4, 8/4, 10/4 and 12/4