There are a total of 22 students in the class. Out of these, 2 have both a brother and a sister, and 4 have neither a brother nor a sister. So, there are 16 students who have either a brother or a sister.
Out of these 16, 2 have both a brother and a sister. So, there are 14 students who have either a brother or a sister but not both.
Out of these 14, 2 have a sister and a brother, so there are 12 students who have a sister but not a brother.
Therefore, the probability that a student has a brother given that they have a sister is 0, as none of the students who have a sister also have a brother.
In a class of students, the following data table summarizes how many students have a brother or a sister. What is the probability that a student has a brother given that they have a sister?
Has a brother Does not have a brother
Has a sister 2 3
Does not have a sister 4 13
2 answers
In a class of students, the following data table summarizes how many students passed a test and complete the homework due the day of the test. What is the probability that a student who passed the test completed the homework?
Passed the test Failed the test
Completed the homework 19. 2
Did not complete the homework 3 6
Passed the test Failed the test
Completed the homework 19. 2
Did not complete the homework 3 6