How to match the perfect value with oil paint. Munsell color mixing series 1

I use Titanium white, Ivory black, and Raw umber to create the perfect value 5. I go through the thought process and why I am doing it this certain way and how to navigate too light or too dark of values. It helps to have a reference to compare like I used a Munsell color book student edition 2 as my reference to mix the right value. Use oil paint and a painting knife to figure out the pure neutral gray color.