Q6 · General Aptitude · MCQ · 2 marks
Among 150 faculty members in an institute, 55 are connected with each other through Facebook and 85 are connected through WhatsApp. 30 faculty members do not have Facebook or WhatsApp accounts.
The number of faculty members connected only through Facebook accounts is ______________.
- (A)35
- (B)45
- (C)65
- (D)90
Answer (official key): A
Solution
Total faculty members:
Faculty members with neither Facebook nor WhatsApp:
So faculty members having at least one of the two accounts:
Let be Facebook users and be WhatsApp users.
Given:
Using inclusion-exclusion:
Only Facebook users:
Therefore, the correct answer is Option A.
