Use the table to answer the question.

Grade Level
Apple Preference Elementary School Students Middle School Students High School Students Total
Likes apples 85 92 97 274
Dislikes apples 15 8 3 26
Total 100 100 100 300
Let A be the event that a student likes apples. Let B be the event that a student is in middle school. Based on the data in the table, are events A and B independent?

(1 point)
Responses

Yes; the events are independent because P(A)=P(A|B)=0.90.
Yes; the events are independent because cap p times cap A is equal to cap p times open paren cap A divides cap b close paren is equal to 0 point 9 0.

No; the events are dependent because P(A)=0.913 and P(A|B)=0.92.
No; the events are dependent because cap p times cap A is equal to 0 point 9 1 3 and cap p times open paren cap A divides cap b close paren is equal to 0 point 9 2.

No; the events are dependent because P(A)=0.93 and P(A∩B)=0.91.
No; the events are dependent because cap p times cap A is equal to 0 point 9 3 and P(A∩B)=0.91.

Yes; the events are independent because P(A)=P(A∩B)=0.92.

1 answer

To determine if events A (a student likes apples) and B (a student is in middle school) are independent, we need to calculate the probabilities P(A), P(B), and P(A|B).

  1. Calculate P(A) (the probability that a student likes apples): \[ P(A) = \frac{\text{Total who like apples}}{\text{Total students}} = \frac{274}{300} \approx 0.913 \]

  2. Calculate P(B) (the probability that a student is in middle school): \[ P(B) = \frac{\text{Total middle school students}}{\text{Total students}} = \frac{100}{300} = \frac{1}{3} \approx 0.333 \]

  3. Calculate P(A ∩ B) (the probability that a student likes apples and is in middle school): \[ P(A \cap B) = \frac{\text{Middle school students who like apples}}{\text{Total students}} = \frac{92}{300} \approx 0.307 \]

  4. Calculate P(A|B) (the probability that a student likes apples given that the student is in middle school): \[ P(A|B) = \frac{P(A \cap B)}{P(B)} \approx \frac{92/300}{100/300} = \frac{92}{100} = 0.92 \]

Now, check if \( P(A) \) is equal to \( P(A|B) \):

  • \( P(A) \approx 0.913 \)
  • \( P(A|B) = 0.92 \)

Since \( P(A) \) is not equal to \( P(A|B) \), events A and B are dependent.

Therefore, the correct response is:

No; the events are dependent because P(A)=0.913 and P(A|B)=0.92.