I Still Don't Understand Algebra

Schatz: What is M+3-T ?

Me: Five?

Schatz: No.

Me: Eleven?

Scahtz: Now you are just guessing.

Me: I don't know!

Schatz: It's a color.

Me: Pink?

Schatz (shouting the answer): Chameleon!

Me: Chameleon? That's not a color!

Schatz: It's all the colors!