Machine-translated by Google. Questions are authored in English.
Top

Discussion

In a company with 100 employees, a survey finds that 45 read Business Today, 55 read Economic Times, and 15 read neither. How many employees read both magazines?

  • A.5
  • B.10
  • C.15
  • D.20

Answer: B

Correct answer: 15

If 15 of the 100 employees read neither magazine, then the number reading at least one is

\[n(BT \cup ET) = 100 - 15 = 85\]

Apply the inclusion–exclusion principle:

\[n(BT \cup ET) = n(BT) + n(ET) - n(BT \cap ET)\]

\[85 = 45 + 55 - n(BT \cap ET) \quad\Longrightarrow\quad n(BT \cap ET) = 100 - 85 = 15\]

So 15 employees read both.

No comment is present. Be the first to comment.
Loading…

Post your comment

Please log in or register to post a comment.