Question

http://prntscr.com/b0emfy

Answer 1

some of the answers make so sense no matter what

Answer 2

rae-jay im lost though

Answer 3

A and B are independent if \[P(A|B)=P(A)\]
before we go further, pick out the two that make no sense at all

Answer 4

...

Answer 5

you need a hint?

Answer 6

yes ';c

Answer 7

A is "going to high school"
B is "GPA above 30"
look at what i wrote above and see what should be on the right hand side of the equal sign, whether it is true or not

Answer 8

so b and d are incorrect

Answer 9

no

Answer 10

on the right hand side should be \(P(A)\)

Answer 11

where A is "go to high school"

Answer 12

and on the left its a and b

Answer 13

look at your choices
which ones have, on the right, \(P(\text{high school})\)?

Answer 14

B and C

Answer 15

whew!

Answer 16

so it has to be one of those two

Answer 17

and now we need to check to see if they are equal or not!

Answer 18

wait why would it be p(high school)? because its listed first?

Answer 19

yes that is exactly why

Answer 20

in english
A and B are independent of the probability of A given B is equal to the probability of A

Answer 21

in math
A and B are independent means \[P(A|B)=P(A)\]

Answer 22

so now we need to compute those two numbers, and see if they are equal or not
first lets compute \(P(A)\) which is straight forward
how many people are there total?

Answer 23

http://prntscr.com/b0erht i like this one better

Answer 24

too bad
you don't have the numbers you need to check that

Answer 25

ARGGGGGG *rips hair out*

Answer 26

so lets continue before you go bald
how many people total?

Answer 27

it tells you, you don't have to compute it!

Answer 28

100 ppl total

Answer 29

right
and of those, what is the total number that go to high school?

Answer 30

60

Answer 31

right
so \[P(A)=\frac{60}{100}=\frac{6}{10}=0.6\]

Answer 32

yes

Answer 33

?ok now for \[P(A|B)\] how many people total have a GPA above 30

Answer 34

not in college?

Answer 35

total

Answer 36

40/100

Answer 37

your killing me
i didn't ask for a probability, just the number of people that had a GPA above 30

Answer 38

rae-jay this is NOT my forte. its always been my weakness. now please bare with me.

Answer 39

40

Answer 40

right!

Answer 41

and of those 40, how many are in high school?

Answer 42

14

Answer 43

ok good

Answer 44

so the proibability you are in high school given that your gpa is above 3.0 is \[P(A|B)=\frac{14}{40}\]

Answer 45

now we can answer
is \[P(A|B)=P(A)\] i. e is \[\frac{14}{40}=\frac{60}{100}\]?

Answer 46

hint, they are not equal

Answer 47

wait | is / ?

Answer 48

?

Answer 49

see how its a|b does that mean a/b because you made it a fraction.

Answer 50

the question is, does \(\frac{14}{40}=\frac{60}{100}\)
if so, they are independent
if not, they are dependent

Answer 51

oh no hold on your are confused

Answer 52

the probability is a fraction, yes, it is a number

Answer 53

a/b is a|b

Answer 54

the vertical line in \[P(A|B)\] reads "the probability of A given B" A and B are events, not numbers

Answer 55

A GIVEN B?!??!?!?!??

Answer 56

let me right it in english \[P(\text{high school}|\text{GPA above 3.0})=\frac{14}{40}\]

Answer 57

that reads as follows
the probability you are in high school, given that your gpa is above 3.0 is \(\frac{14}{40}\)

Answer 58

etjeriogjreioiofvguruiwortirtoirugiovjfiogr *stops banging head on keyboard* ohhhhhhhh i get it

Answer 59

whew

Answer 60

so D right?

Answer 61

jkjk no need to fret its B

Answer 62

so , since they are not equal
i.e. since the probability you are in high school given your gpa is above 3.0 is not the same as the probability you are in high school, the answer is ...

Answer 63

yeah B

Answer 64

that was like pulling teeth, but if you look at your picture you can do it with your eyes

Answer 65

rae-jay i have a mind of a 5 year old for this, you already know. but thank you so much.

Answer 66

yw

Answer 67

I love dogs