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A classroom of 18 students has 5 students that have a brother and 7 students who have a sisters. 9 students have neither. How do you figure the probability of a student that has a brother does not has a sister

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To figure out the probability of a student who has a brother not having a sister, we need to consider the number of students who have a brother and do not have a sister.

Given the information provided:
- There are 18 students in total.
- 5 students have a brother.
- 7 students have a sister.
- 9 students have neither.

To find the number of students who have a brother without a sister, we need to subtract the number of students who have both a brother and a sister from the total number of students with a brother.

Number of students who have a brother and a sister = 0 (since it is not stated in the given information)

Number of students who have a brother without a sister = 5 - 0 = 5

Therefore, there are 5 students who have a brother without a sister.

To calculate the probability, we divide the number of favorable outcomes (students who have a brother without a sister) by the total number of possible outcomes (total number of students with a brother).

Probability of a student who has a brother not having a sister = Number of students who have a brother without a sister / Number of students who have a brother

Probability = 5 / 5 = 1

The probability of a student who has a brother not having a sister is 1 or 100%.
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