I'm visiting an unfamiliar state. This state has a sales tax of 6.1% but I don't know this. All I know is the tax rate is of the form a.b% where a and b are single digits.

I buy an item at a store and am able to deduce the tax rate from the item's price and the tax amount as listed on the receipt.

What is the minimum cost of the item that would allow me to make such a deduction?

Note: The tax amount listed on the receipt is rounded to the nearest cent.