EduFarming
Your list · 0हिं

Type at least two letters. Press Esc to close.

↑↓ navigate↵ openTAB cycle filter

Venn Diagrams · Question 51 of 65

Question 51

MediumOriginal question

Every one of the 62 members of a reading circle reads at least one of three magazines: a science magazine, a sports magazine and a travel magazine. 9 read both the science and the sports magazine, 7 read both the science and the travel magazine, 8 read both the sports and the travel magazine (each count includes those who read all three), and 3 read all three. How many members read exactly one magazine?

Options for question 51

Show the answer and explanation
CorrectNot quiteAnswer C

Correct answer: C

Explanation

  1. Exactly two =9+7+8−3×3=15= 9 + 7 + 8 - 3 \times 3 = 15.

  2. All three =3= 3.

  3. Exactly one =62−15−3=44= 62 - 15 - 3 = 44.

Worth noting

38 subtracts the raw pair counts (24) instead of exactly two; 35 subtracts them and the 3 as well. Both over-remove the centre.

Concept
Exactly one = total − exactly two − all three
Typical time
70 s
Your time
—
The rule this testsCounting with overlapping sets
Practise this chapter →

Ten questions from Venn Diagrams, at your own pace.

Practise this chapter →

Ten questions from Venn Diagrams, at your own pace.

Practise this chapterAll 65 questions in Venn DiagramsRevise the notes for Venn Diagrams