Home » Aptitude » Sets and Functions » Question
  1. In a group of 70 people, 37 like coffee, 52 like tea and each person likes at least one of the two drinks. How many people like both coffee and tea?
    1. 19
    2. 17
    3. 23
    4. 21
Correct Option: A

Let P = set of people who like coffee and Q = set of people like tea.
Then, P ∪ Q = set of people who like at least one of the two drinks.
And P ∩ Q = set of people who like both the drinks.
Given in the question,
n(P) = 37, n(Q) = 52, n(P ∪ Q) = 70.
Use the below formula,
n(P ∪ Q) = n(P) + n(Q) – n(P ∩ Q)
Put the value from the given question,
70 = 37 + 52 – n(P ∩ Q)
⇒ n(P ∩ Q) = 89 – 70 = 19.
∴ 19 people like both coffee and tea.



Your comments will be displayed only after manual approval.