Final answer:
To calculate the final selling price of a ring marked up by 150% and including 8% sales tax, multiply the original price by 1.50 to find the markup amount, then add this to the original price for the pre-tax selling price. Next, calculate sales tax by multiplying the pre-tax selling price by 0.08, and add it to the pre-tax selling price for the total cost. The final selling price is $337.50, which is not listed in the given options.
Step-by-step explanation:
To calculate the selling price of the ring after a 150% markup, we first need to determine the amount of the markup. The markup is calculated on the purchase price of the ring, which is $125. To find the markup amount, we can multiply the purchase price by the markup percentage, expressed as a decimal:
$125 \(\times\) 1.50 = $187.50 (markup amount)
Adding the markup amount to the original purchase price gives us the pre-tax selling price:
$125 + $187.50 = $312.50 (pre-tax selling price)
Next, we need to calculate the sales tax which is 8%. We convert the percent to a decimal and multiply by the pre-tax selling price:
$312.50 \(\times\) 0.08 = $25.00 (sales tax)
Finally, we add the pre-tax selling price and the sales tax to find the final selling price:
$312.50 + $25.00 = $337.50
The final selling price of the ring, including sales tax, is $337.50, which means the correct answer is none of the options provided.