Final answer:
To find the sale price of the shirt, subtract the discount amount from the original price.
Step-by-step explanation:
To find the sale price of the shirt, we need to subtract the discount amount from the original price. Since the shirt is on sale for 30 percent off its original price, we can calculate the sale price using the expression: S - 0.30S, which simplifies to 0.70S. Therefore, the expression that does not represent the sale price of the shirt is S + 0.30S or 1.30S. The question asks which expression does not represent the sale price of the shirt given it is on sale for 30 percent off its original price, S. The sale price of the shirt can be represented by the expression 0.70S, since you are taking 70 percent (100 percent - 30 percent) of the original price, S. This expression, 0.70S, calculates 70 percent of S, giving the sale price after the discount is applied. Alternatively, one could find the amount of the discount by calculating 0.30S and then subtracting that from the original price, resulting in an expression S - 0.30S. Any expression that does not equivalent to these two forms does not correctly represent the sale price of the shirt.