Depending on the color, the math may work out that the amount of particular colorant in the formula divides down so small the dispenser can't shoot it - which is why a Color To Go Jug will indeed sometimes have a different formula vs. a quart, a gallon or a 5. And why mixing small samples can be very different from mixing up a large 5 gallon container.
There is more than one way to mix a color so it meets a certain standard of "match" which is why the varying formulas for one color is industry acceptable.
You can find a gray from every hue family in the spectrum. In every color collection. Based on chromaticity values you can determine a color's hue/value/chroma notation. Grayish's color notation directly from Sherwin Williams itself is 4.32 YR (yellow-red hue) / 8.16 value / 0.48 chroma.
When we run the notation numbers here at The Land of Color we come up with slightly different numbers, but Grayish still ends up smack in the middle of the yellow-red hue family.
Here's and example of chromatic grays across the spectrum along with their color notations. These are Dunn-Edwards colors and Dunn-Edwards color notations.
Here's the blog post that goes with it that explains why so many have the misconception that gray only comes from blue, green or purple hue parents.
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