This is an interesting
mental magic that is absolutely easy to do. The mentalist places a
black disc on the table stating that it a prediction. Now a plastic
board is brought forward that has numbers from 1 to 4. Any number
is selected by a spectator (no force). The board is turned over to
show four colored spots. The color that falls on the selected number
is noted. The disc is turned over to show that it has the same colored
spot on the reverse!