Final answer:
The total cost of the speaker after-tax is $48.15.
Step-by-step explanation:
To find the total cost of the speaker after-tax, we need to calculate the amount of sales tax first. The sales tax is given as 7% of the price of the speaker, which is $45. To find the sales tax amount:
Sales Tax = 7% × $45 = $3.15
The total cost of the speaker after-tax is the sum of the price of the speaker and the sales tax amount:
Total Cost = $45 + $3.15 = $48.15
Learn more about Calculating total cost with sales tax