Final answer:
The percent decrease in the price of the running shoes is calculated as 30% using the formula for percent decrease based on the difference between the original and new prices.
Step-by-step explanation:
To find the percent decrease in the cost of the running shoes, we can use the formula:
Percent Decrease = \((\frac{Original Price - New Price}{Original Price}) \times 100\)%
Applying the formula with the given values:
Original Price = $50
New Price = $35
Percent Decrease = \((\frac{50 - 35}{50}) \times 100\)%
Percent Decrease = \((\frac{15}{50}) \times 100\)% = 30%
The percent decrease for the shoes is 30%.