Example 1: Below is a membership roster for a school club. The roster contains the first name, gender and class of each club member. First Name Gender Class Beth Female Freshman Caleb Male Freshman John Male Freshman Jorge Male Sophomore Mary Female Sophomore Lucy Female Sophomore Abby Female Junior Rob Male Junior Sam Male Jnnior Will Male Senior Jada Female Senior Joe Male Senior Kelly Female Senior A person in the club is to be chosen to travel to a national convention. 1.
How many females are there to choose from?
2.
How many seniors are there to choose from?
3.
How many senior females are there to choose from?
4.
After the choice is made, you are told that the chosen person was a senior or a female (or both). How many club members are there who fit this description?
Special Note: In mathematics, the word “or” is most always used to mean “one or the other or both”. This is known as an inclusive “or”. Throughout the rest of this activity, always use this interpretation when asked to answer questions about the occurrence of one event or another. 5.
Explain the relationship between the answer to question 4 and the answers to questions 1 through 3.