How to match the three primary colors with white?

Three primary colors don't match white.

The three primary colors are not worthy of white, because black, white and gray belong to colorless system. But the three primary colors of colored light (red, green and blue), namely RGB, can bring out white. White can be a mixture of three equal amounts of red, medium green and dark blue. This will be achieved by using optical elements, but not by adjusting pigments.

"Three primary colors" refer to the three basic colors that cannot be decomposed any more. Generally speaking, there are two kinds of "three primary colors": color primary colors and optical primary colors. Among them, "three primary colors" refer to magenta, yellow and cyan. The three primary colors can mix the colors of all pigments and add up to black.