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2.3 Probability

2.3 Probability

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Question 117
a.

Two events EEE and FFF have probabilities P(E)=pP(E) = pP(E)=p and P(F)=qP(F) = qP(F)=q. Express P(E∪F)P(E \cup F)P(E∪F) in terms of ppp and qqq when: (i) EEE and FFF are mutually exclusive, (ii) EEE and FFF are independent.

[2]
b.

In a soil quality assessment, let AAA be the event that a sample contains Lead and BBB be the event that it contains Mercury. It is known that

P(A∩B′)=0.45,P(B)=0.35andP(A∣B)=0.6 P(A \cap B') = 0.45, \quad P(B) = 0.35 \quad \text{and} \quad P(A|B) = 0.6 P(A∩B′)=0.45,P(B)=0.35andP(A∣B)=0.6

Find the value of: P(A∪B)P(A \cup B)P(A∪B)

[2]
c.

P(A∩B)P(A \cap B)P(A∩B)

[2]
d.

P(A)P(A)P(A)

[2]
Markscheme

2.3 Probability Questions

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

200 exam-style questions on OCR (MEI) A Level Maths 2.3 Probability, covering 2.3.1 Calculate the probability of an event, 2.3.2 Complementary events, 2.3.3 Expected frequency of an event, 2.3.4 Diagrams to calculate probabilities, 2.3.5 Mutually exclusive and independent events, 2.3.6 Add probabilities for mutually exclusive events, 2.3.7 Multiply probabilities for independent events, 2.3.8 Mutually exclusive and independent events (notation) (A-level only), 2.3.9 Venn diagrams for probabilities (A-level only), 2.3.10 Conditional probabilities (A-level only), and 2.3.11 Independence via conditional probability (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.

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