Question

A two-way frequency table shows grades for students in college and students in high school.

High school College Total
GPA above 3.0 14 26 40
GPA below 3.0 46 14 60
60 40 100


Based on this data, are "being in high school" and "GPA above 3.0" independent events?
Yes, P(high school | GPA above 3.0) = P(high school)

Yes, P(high school | GPA above 3.0) = P(GPA above 3.0)

No, P(high school | GPA above 3.0) ≠ P(high school)

No, P(high school | GPA above 3.0) ≠ P(GPA above 3.0)
@myin

Answer 1

@Disco619

Answer 2

@math&ing001

Answer 3

@mathmale

Answer 4

woohoo: Have you actually tried calculating the probabilities listed in those four possible answers?

Answer 5

no i dont know whats independent probability

Answer 6

@Mathbreaker

Answer 7

In probability theory, to say that two events are independent (alternatively called statistically independent or stochastically independent ) means that the occurrence of one does not affect the probability of the other.
This means that if its independent, a tree diagram would not have a continual representation. However in this case, its clear that one event has an effect on the other.
I think this is enough information for you to conclude to an answer. All the best :)

Answer 8

the second one?

Answer 9

@mathmale

Answer 10

As I hinted before, you need to calculate the probabilities involved in the four possible answer choices. I've done this and have found that one of the answers is correct.

You are given data in that table and need to know how to find conditional probabilities from that data.

Look at the first possible answer. Can you find each of the two probabilities involved in Yes, P(high school | GPA above 3.0) = P(high school) ?

What is the probability that a student chosen at random from a group of 100 people is in high school? If you know how to do that, you're on the right track. If not, then it's back to basic probability calculations before you can determine whether or not events are independent or not.

Answer 11

so the first one?

Answer 12

@mathmale plsssss i reaaaly need to know!!??

Answer 13

No point in guessing, woohoo. Please look at what I typed above, especially the third paragraph. What is P(high school)? what is P(high school | GPA above 3.0)?

Answer 14

@mathmale

Answer 15

is it the third one plsss?

Answer 16

Before I respond, please explain your reasoning in choosing the 3rd possible answer.