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In a class of 25 students, 14 have a brother and 17 have a sister. There are 5 students who do not have any siblings. What is the probability that a student who has a brother also has a sister?

In a class of 25 students, 14 have a brother and 17 have a sister. There are 5 students-example-1
User Yrineu Rodrigues
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1 Answer

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Final answer:

The probability that a student who has a brother also has a sister is 1.4286.

Step-by-step explanation:

To find the probability that a student who has a brother also has a sister, we can use conditional probability.

The number of students who have a brother is given as 14, and the number of students who have a sister is given as 17.

The number of students who have both a brother and a sister can be found by subtracting the number of students who have no siblings from the total number of students: 25 - 5 = 20.

Therefore, the probability that a student who has a brother also has a sister is 20/14 = 1.4286.