Final answer:
The total cost C for an item priced at x dollars with a 7.25% sales tax is calculated using the formula C = x × 1.0725. You start by converting the sales tax percentage into a decimal and multiply it by the item's price, then add the result to the original price to get the total.
Step-by-step explanation:
Finding the Total Cost with Sales Tax
To find the total cost C of an item selling for x dollars with a sales tax rate of 7.25%, you need to add the original cost of the item to the cost of the sales tax. The sales tax can be calculated by converting the percentage to a decimal and then multiplying it by the item's price.
Thus, the formula to calculate the total cost with sales tax is: C = x + (x × (sales tax rate in decimal form)). In the case of a 7.25% sales tax rate, you convert 7.25% to a decimal (0.0725) and then multiply by x (the price of the item). The correct formula for calculating the total cost is:
C = x × 1.0725
For instance, if you purchase an item for $100 with a 7.25% sales tax, the total amount of sales tax would be $100 × 0.0725, which equals $7.25. Hence, the total cost of the item would be $100 + $7.25, equal to $107.25.