The way I did it was doing 12/20 to find what percentage of 12 is 20. I found out that was 60%, which means that the sweater's price was reduced by 40%. However, there are other ways of doing this.
A better way is solving for percentage is: initial value - final value / initial value
Step-by-step explanation: In special case isosceles right triangles the hypotenuse is always equal to a · √2. With a=5√2 we can set up the equation 5√2 · √2 = 10.
