In the membrane of human red blood cell, the ratio of the mass of protein (average MW = 50000) to phospholipid (average MW = 800) to cholesterol (MW = 386) is about 2 : 1 ; 1. How many lipid molecules are there for every protein molecule?

~ 96 Lipid Molecules

Using these average molecular weights, there are 96 lipid molecules (phospholipid
+ cholesterol) for every protein molecule

{[(50,000/800) + (50,000/386)]/2 = 96}.