Question

There are thirteen boys and fifteen girls in a class. The teacher randomly selects one student to answer a question. Later, the teacher selects a different student to answer another question. What is the probability that the first student is a boy and the second a girl? Explain.

Answer 1

Explanation:

To solve this problem, we need to calculate the probability of the first student being a boy and the second student being a girl.

There are a total of 13 boys and 15 girls in the class, making a total of 28 students.

The probability of the first student being a boy is given by:

P(boy) = Number of boys / Total number of students = 13 / 28

After the first student is selected, there are now 27 students remaining (since one student has already been selected). Out of these 27 students, there are still 15 girls remaining.

The probability of the second student being a girl, given that the first student was a boy, is given by:

P(girl|boy) = Number of girls / Remaining number of students = 15 / 27

To find the probability of both events occurring (the first student being a boy and the second student being a girl), we multiply the individual probabilities:

P(boy and girl) = P(boy) * P(girl|boy) = (13/28) * (15/27)

Calculating this expression:

P(boy and girl) ≈ 0.2041

Therefore, the probability that the first student is a boy and the second student is a girl is approximately 0.2041 or 20.41%.