15% off $32.50 means a reduction of 15% x 32.5 = $4.875
And the paid cost is 32.5 - 4.875 = $27.625
Another method: the discount is 15% of te 100%, that means he will be
only 85% (100% - 15%) of the 32.5,, then the paid price will be 32.5 x 85%
or 32.5 x 0.85 = $27.625