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2.3 Probability

2.3 Probability

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Question 111
43%

An astrophysicist is monitoring a space telescope's imaging sensors for three types of interference: Cosmic Ray hits (CCC), Solar Flares (SSS), and Thermal Noise spikes (TTT). The probabilities of these events occurring during a specific exposure window are provided below using set notation:

  • P(C∩S′)=0.147P(C \cap S') = 0.147P(C∩S′)=0.147
  • P(C∩S)=0.062P(C \cap S) = 0.062P(C∩S)=0.062
  • P(S∩C′∩T′)=0.224P(S \cap C' \cap T') = 0.224P(S∩C′∩T′)=0.224
  • P(S∩T)=0.088P(S \cap T) = 0.088P(S∩T)=0.088
  • P(T∩S′)=0.319P(T \cap S') = 0.319P(T∩S′)=0.319

It is known that the telescope's shielding prevents Cosmic Ray hits and Thermal Noise spikes from occurring simultaneously, making them mutually exclusive events (C∩T=∅C \cap T = \emptysetC∩T=∅).

Given that the probability of an exposure having no interference is represented by www, determine the value of www.

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Markscheme

2.3 Probability Questions

  1. A Level
  2. /Maths
  3. /2.3 Probability

200 exam-style questions on OCR A Level Maths 2.3 Probability, covering 2.3.1 Mutually exclusive and independent events, 2.3.2 Diagrams to assist probability calculations, 2.3.3 Conditional probability (A-level only), 2.3.4 Conditional probability from first principles (A-level only), and 2.3.5 Modelling with probability. Each one has a worked solution and a mark scheme showing where the marks go.

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