Question

Which information is not necessary to solve this problem? Five members of a club each brought 2 friends to their first meeting. There are 23 people in the club. How many member's friends came to the meeting? There are 23 people in the club. Five members brought friends. Some members brought 2 friends each.

Answer 1

" There are 23 people in the club."

Explanation:

We want to know how many member's friends came to the meeting.

We know that:

There are 23 people in the club

5 members of the club, invited 2 friends each.

So we have 5 times 2 friends invited:

Then there are 5*2 = 10 people invited to the first meeting.

Notice that the fact that there are 23 people in the club is never used, them the information that is not necessary to solve this problem is " There are 23 people in the club."