How do I force a value in a set on random variables?

Ok I'll try to explain this situation. I know how to pick random values for a sprite and or animation frame but How would you pick a random variable if lets say you wanted to limit or filter the values to an option - lets say their is a menu and its options are colors. I'm picking 4 random colors but when RED is selected at least one of the 4 items is RED.

I have my sets of frames all ordered the same so lets say RED is 1-10 orange is 11-20 yellow is 21-30 etc.

Any Ideas?

So you are displaying 4 sprites of random colors and you need at least one of the sprites to be red?

The easiest solution is to do something like this (assuming that frame 0 is empty/transparent, and frames 1-10 are red):

System pick random sprite
..Sprite Set animation frame to int(random(1,11))

Sprite animation frame = 0
..Sprite Set animation frame to int(random(1,41))