A toy company manufactures a spinning game and needs to decide what probabilities are involved in the game. The plastic arrow on the spinner stops rotating to point at a colour that will determine what happens next. Knowing these probabilities will help determine how easy or difficult it is for a person to win the game and how long the average game will last. Are each of the following probability assignments possible? Why or why not?

Probabilities of: Red Yellow Green Blue 0.25 a) 0.25 0.25 0.25 b) 0.10 0.20 0.30 0.40 0.20 0.30 0.40 0.50 d) 1.00 -1.50 e) 0.10 0.20 1.20