A biased spinner can only land on one of the numbers 1, 2, 3 or 4. The random variable X X\,X represents the number that the spinner lands on after a single spin and P(X=r)=P(X=r+1)P(X = r) = P(X = r + 1)P(X=r)=P(X=r+1) for r=1,3r = 1, 3r=1,3
Given that P(X=1)=0.16P(X = 1) = 0.16P(X=1)=0.16
find the complete probability distribution for XXX.
Mark spins the spinner 50 times. Find the probability that the spinner lands on the number 4 more than 20 times.
The random variable Y=8−3XY = 8 - 3XY=8−3X. Find P(Y+X≥1)P(Y + X \geq 1)P(Y+X≥1)
390 exam-style questions on OCR (MEI) A Level Maths 2.4 Probability Distributions, covering 2.4.1 Recognise binomial situations, 2.4.2 Probability of success p, 2.4.3 Calculate binomial probabilities, 2.4.4 Mean of the binomial distribution, 2.4.5 Expected frequencies for binomial, 2.4.6 Probability functions and discrete random variables, 2.4.7 Numerical probabilities for a simple distribution, 2.4.8 Normal distribution as a model (A-level only), 2.4.9 Shape of the Normal curve (A-level only), 2.4.10 Linear transformation and standardising (A-level only), 2.4.11 Symmetry and inflection of Normal curve (A-level only), 2.4.12 Calculate probabilities from a Normal distribution (A-level only), 2.4.13 Model with probability distributions, and 2.4 Probability Distributions. Each one has a worked solution and a mark scheme showing where the marks go.