Yellow and black: What Color Do They Make?

Olive

Yellow + black = olive. With more yellow you get mustard; with more black, dark olive.

More shades from the same colors

Mustard2 parts yellow + 1 part blackDark olive1 part yellow + 2 parts blackLight oliveolive + whiteDark oliveolive + black

Put the color down first and add black little by little: a little black darkens a lot.
To darken without dulling the color, try a darker shade of the same color instead of black.

What color do yellow and black make?

Yellow + black, in equal parts, make olive. With more yellow it leans toward mustard, and with more black, toward dark olive.

What ratio of yellow and black should I use?

Half and half makes olive. 2 parts yellow to 1 part black gives mustard; 1 part yellow to 2 parts black gives dark olive.

How do I make olive lighter or darker?

Add white little by little to lighten it (light olive) or a little black to darken it (dark olive).

Is it the same with watercolor, acrylic and oil?

The result is similar. Watercolor looks lighter because the white paper shows through; acrylic gets a little darker as it dries.