Final answer:
The percentage decrease in the price of the shirt is calculated by dividing the decrease in price by the original price, then multiplying by 100 and rounding to the nearest percent if required.
Step-by-step explanation:
To calculate the percentage decrease in the price of the shirt, first determine the amount of the decrease. Subtract the sale price from the original price: $35.19 - $28.15 = $7.04. Then, divide the decrease by the original price: $7.04 / $35.19. To find the percentage, multiply the result by 100: ($7.04 / $35.19) × 100.
The computation will give you the percentage decrease which can be rounded to the nearest percent if necessary.