Question

An individual is planning a trip to a baseball game for 20 people. Of the people planning to go to the baseball game, 11 can go on Saturday and 14 can go on Sunday, some of them can go on both days. How many people can only go to the game on Saturday?

Answer 1

6 people

Explanation:

Suppose A represents the event of going on Saturday,

B represents the event of going on Sunday,

According to the question,

n(A)=11

n(B)=14

n(A∪B)=20

We know that,

n(A∪B) = n(A) + n(B) - n(A∩B)

By substituting values,

20 = 11 + 14 - n(A∩B)

⇒ n(A∩B) = 25 - 20 = 5,

Hence, the number of people who can only go to the game on Saturday = n(A) - n(A∩B) = 11 - 5 = 6.