Final answer:
To find the sales tax rate, divide the amount of sales tax by the cost of the item before tax and multiply by 100 to express it as a percentage.
Step-by-step explanation:
To find the sales tax rate, divide the amount of sales tax by the cost of the item before tax and multiply by 100 to express it as a percentage. In this case, the amount of sales tax is $32.90 and the cost before tax is $470. So, the sales tax rate can be calculated as:
(32.90/470) * 100 = 0.07 * 100 = 7%