I did understand, and wrong is wrong. Man up, admit it and get over it.
PS, Human hearing is LOGARITHMIC (curved) in nature as sensetivity to sound frequencies (more for mid, less for low end and high end sounds), it is not expressed in a ratio format (which is direct and linear in form) So while dB A weighted Logarithmic describes human hearing, dB used in NRR Ratios does not perscribe the response to human hearing.
So to answer your question, you are wrong again. and 50 can be half, or 1/4 or 1/8 of 100, it all depends at what frequency you are measuring (100,1000,10000Hz). Human hearing is Logarithmic in nature. It is not a Ratio.
Earlier you told me I was making a fool of myself? Judging by what you wrote, I have no fear of that happening in conversing with you on this topic.