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4024/11 Oct/Nov 2021, Question 19: Set Notation

Cambridge O Level Mathematics 4024 · Paper 11 (Non-calculator) · Non-calculator · 3 marks

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The question, in short

Given sets ℰ, X and Y, work out a set intersection, a probability involving union and complement, and shade a Venn diagram region.

Summarised in our own words. Use the official paper for the exact wording and the diagram.

Part (ai) · 1 mark

List the elements shared by X and Y.

  1. 1X ∩ Y = numbers in both sets = {2, 3, 5}

Answer2, 3, 5

Part (aii) · 1 mark

For k picked at random from ℰ, work out the chance k lies outside X ∪ Y.

  1. 1X ∪ Y = {1, 2, 3, 4, 5, 6, 7, 11}
  2. 2Not in X ∪ Y: 8, 9, 10, 12, so 4 numbers
  3. 3P(k ∉ X ∪ Y) = 4/12

Answer4/12

Part (b) · 1 mark

Shade the region for A ∩ (B ∪ C)′ on the three-circle Venn diagram.

  1. 1(B ∪ C)′ is everything outside B and C
  2. 2Shade the part of A that is outside both B and C

AnswerShaded: the part of A outside both B and C

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Also searched as: 4024/11/O/N/21 · 4024_w21_qp_11 · 4024 w21 11 · question 19.
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