The Linux Foundation Individual Supporter + exam discount

Hello,

I have a discount code for the cks exam. If I buy “The Linux Foundation Individual Supporter”, does the discount add up to the benefit of -$ 100 for the exam?
400 - 100 * 50% = 150
or
400 * 50% - 100 = 100
or
400 * 50% or 400 - 100