Edexcel AS Paper 2 2018 June — Question 5

Exam BoardEdexcel
ModuleAS Paper 2 (AS Paper 2)
Year2018
SessionJune
TopicDiscrete Probability Distributions
TypeConstruct probability distribution from scenario

5. A biased spinner can only land on one of the numbers \(1,2,3\) or 4 . The random variable \(X\) represents the number that the spinner lands on after a single spin and \(\mathrm { P } ( X = r ) = \mathrm { P } ( X = r + 2 )\) for \(r = 1,2\) Given that \(\mathrm { P } ( X = 2 ) = 0.35\)
  1. find the complete probability distribution of \(X\). Ambroh spins the spinner 60 times.
  2. Find the probability that more than half of the spins land on the number 4 Give your answer to 3 significant figures. The random variable \(Y = \frac { 12 } { X }\)
  3. Find \(\mathrm { P } ( Y - X \leqslant 4 )\)