Percentage Discount given an Original Price of $57.14 and a Sale Price of $40

Discount Rate = 1 –  
Discount Rate = 1 – 0.7
Discount Rate = 0.3
0.3 Converted to a Percent: 0.3 = 30%
Percentage Discount given an Original Price of $57.14 and a Sale Price of $40 = 30%
Note: Reduction in Price = $57.14 – $40 = $17.14