Answer:
a. 44.6%
b. "In this class, 32.1% of students have a brother, 57.1% have a sister, and 14.3% have both a brother and a sister. Therefore, the probability of a student having a sister given that they have a brother is approximately 44.6%."
Step-by-step explanation:
a. The probability of S given B is the probability of having a sister given that you have a brother. This is calculated by dividing the percentage of students who have both a brother and a sister (14.3%) by the percentage of students who have a brother (32.1%). This gives us a probability of approximately 44.6%.
b. The teacher could write on the slide: "In this class, 32.1% of students have a brother, 57.1% have a sister, and 14.3% have both a brother and a sister. Therefore, the probability of a student having a sister given that they have a brother is approximately 44.6%."