Register
Mrs. Jones surveys her class of 20 students about their siblings. In the class, 15 have a brother, 16 have a sister, and 12 have both a brother and a sister. What is the probability that a student has
120k views
2 votes
Mrs. Jones surveys her class of 20 students about their siblings. In the class, 15 have a brother, 16 have a sister, and 12 have both a brother and a sister. What is the probability that a student has a brother OR a sister?

User Adrian Baddeley
by
7.9k points

2 Answers

2 votes
about 10 % of people might have a brother or sister 
User Gaurav Aggarwal
by
8.5k points
4 votes
P(Brother or Sister) = .75 + .82 - .65 P(Brother or Sister) = .92 = 92% The reason you subtract the .65 is that scenario does not fit the rule. The rule is the probability of having a brother OR a sister. The .65 represents the kids who have both not either.
User DrSammyD
by
8.5k points
← Prev Question Next Question →

No related questions found

Ask a Question
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Other Questions

What is .725 as a fraction
A bathtub is being filled with water. After 3 minutes 4/5 of the tub is full. Assuming the rate is constant, how much longer will it take to fill the tub?
i have a field 60m long and 110 wide going to be paved i ordered 660000000cm cubed of cement  how thick must the cement be to cover field
Write words to match the expression. 24- ( 6+3)
A dealer sells a certain type of chair and a table for $40. He also sells the same sort of table and a desk for $83 or a chair and a desk for $77. Find the price of a chair, table, and of a desk.
Link Copied!