82(1 - x) = 65.60
82 - 82x = 65.60
82x = 16.4
x = 0.2
The percent of discount is 20%
A isn't true because 513 is at least divisible by 3, so it's not a prime number.
C isn't true because all whole numbers are either prime or composite.
D isn't true because it is neither a imaginary number, fraction, decimal, or unreal number, so therefore it must be a whole number.
B is true, because it is able to be divided by numbers other than one and itself.
