Final answer:
To calculate the recipe cost of mayonnaise and determine the selling price of a turkey cheddar sandwich including sales tax, we sum the costs of ingredients, divide by the target food cost percentage, and add the calculated tax to the selling price.
Step-by-step explanation:
To calculate the recipe cost of mayonnaise from the 'On Cooking' textbook, you would begin by adding up the cost of all the ingredients used to make the mayonnaise. Unfortunately, without the actual recipe and the cost of each ingredient from the textbook, we cannot provide a precise calculation. Once the recipe cost for the mayonnaise is known, you can then incorporate it into the cost of making a turkey cheddar sandwich from the same textbook.
For the turkey cheddar sandwich, after summing up the cost of all ingredients including the previously calculated cost for the mayonnaise, you would apply the desired food cost percentage to determine the selling price. As noted, the food cost is aimed to be 35%. So, if the total cost of ingredients for the sandwich is calculated, you would then divide this by 0.35 to get the selling price. For example, if the total ingredient cost was $2.00, then the selling price would be $2.00 / 0.35 = approximately $5.71.
To include the sales tax, convert the sales tax percentage to a decimal and then multiply by the selling price. If the sales tax is 6%, you would calculate it as 0.06 × $5.71 = approximately $0.34, which you would add to the selling price for a final total.