9709 P62 - Nov 2018 - Q6
2907
A fair red spinner has 4 sides, numbered 1, 2, 3, 4. A fair blue spinner has 3 sides, numbered 1, 2, 3. When a spinner is spun, the score is the number on the side on which it lands. The spinners are spun at the same time. The random variable X denotes the score on the red spinner minus the score on the blue spinner.
- Draw up the probability distribution table for X.
- Find \(\text{Var}(X)\).
- Find the probability that \(X\) is equal to 1, given that \(X\) is non-zero.
