A student is selected at random from a class of 40 students, where 25 are boys and 15 are girls. What is the probability that the student is a girl given that the student is not a boy?
Practice Questions
1 question
Q1
A student is selected at random from a class of 40 students, where 25 are boys and 15 are girls. What is the probability that the student is a girl given that the student is not a boy?
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The total number of students that are not boys is 15 (girls). The probability of selecting a girl given that the student is not a boy is 15/15 = 1.
Questions & Step-by-step Solutions
1 item
Q
Q: A student is selected at random from a class of 40 students, where 25 are boys and 15 are girls. What is the probability that the student is a girl given that the student is not a boy?
Solution: The total number of students that are not boys is 15 (girls). The probability of selecting a girl given that the student is not a boy is 15/15 = 1.
Steps: 7
Step 1: Identify the total number of students in the class, which is 40.
Step 2: Determine how many of those students are boys, which is 25.
Step 3: Calculate the number of students that are not boys. Since there are 40 students and 25 are boys, the number of students that are not boys is 40 - 25 = 15.
Step 4: Recognize that the students who are not boys are all girls, which means there are 15 girls.
Step 5: To find the probability of selecting a girl given that the student is not a boy, use the formula: Probability = (Number of girls) / (Number of students that are not boys).
Step 6: Substitute the numbers into the formula: Probability = 15 / 15.
