Businesses that offer repayment plans for purchases are required by law to disclose the interest rate. But that doesn't mean they go out of their way to let you know what it is. You have to read all the paperwork. Find the interest rate for the following purchase.

For a 312 square-foot family room, you choose carpet that costs $1.49 per square foot. The tax rate is 6.6%, and you're offered 24 payments of $27.64. Round to one decimal place, if necessary.

the interest rate is