what is the expected payback?

One option in a reulette game is to bet $4 on red. (There are 18 red compartments, 18 black compartments, and two compartments that are neither red nor black.) It the ball lands on red, you get to keep the $4 you paid to play the game and you are awarded $4. If the ball lands elsewhere. you are awarded nothing and the $4 that you bet is collected. Find the expected payback for this routette game if you bet $4 on red. W , The expected payback is $[:|. (Round to the nearest cent as needed.)