Question

Algebra 2 Help please? I'll give out medals and become fans
In a previous algebra 2 problem, it told me to make a two- way frequency table. However, in another question, it said to find the probabilities of P(A ∩ B) and P( A ∪ B) and compare. Extremely confused :\ I'm not really sure what to put for A and B either

Answer 1

@ranga

Answer 2

@mathmale

Answer 3

@nikato ?

Answer 4

please helllllpppp :(

Answer 5

Karp

Answer 6

what?

Answer 7

Karp!

Answer 8

ok...

Answer 9

google magikarp

Answer 10

how is Pokemon even remotely related to this?

Answer 11

pokemon relates to everything

Answer 12

@Hero ?

Answer 13

anyone?

Answer 14

ok, we have a table. But what is the question?

Answer 15

The question is: Compare P(A∩B) with P(A∪B), and explain what each probability means in the context of the situation and data you collected.

Answer 16

and do they define A and B ?

Answer 17

no, I think they want me to define A and b, but that's where I get stuck; which ones do I pick for a and b?

Answer 18

can you take a screen shot of the question along with any info they provide?

Answer 19

I'm stuck on number 4

Answer 20

ok. did you answer part 3? if so, what was the answer?

Answer 21

For the third question I put P(Person is a male| Person is 'for') for P(A|B) and I got 4/6, and for the P(B|A) I got 4/10

Answer 22

I'm not sure if that is correct though

Answer 23

P(A | B) is 4/6 = ( A \( \cap \) B)/A= 4/ 6= ⅔ (you should simplify)

P(B|A) = ( A \( \cap \) B)/A = 4/10 = 2/5

so you did it correctly, except for not simplifying

Answer 24

Also, you have defined A and B, so we can do A U B and A ∩ B

Answer 25

I'm not sure what operation to do for the U and the ∩

Answer 26

I didn't really use a formula for number 3

Answer 27

intersection (the ∩ ) means the number of "events" (in this case, votes) that are both (at the same time) "male" and "for"

Answer 28

in other words, the "box" labeled male and for which contains the 4

Answer 29

so.. would it just be 4/20 or 1/5 then?

Answer 30

yes, the Pr ( A ∩ B) is the # of votes in A ∩ B divided by the total number of votes. 4/20 = 1/5

Answer 31

Thank you so much!! What does the U symbol mean though? I think it's called union but i'm not sure what to do with it

Answer 32

union means all events that are either in A or B (but we don't double count)

Answer 33

so... since intersection is 4/20, what exactly would i do with A and B? Some of my textbooks say that I have to do the P(A) * the P(B) and others say that P(AUB) = P(A) + P(b|A)

Answer 34

in this case, we can label each "box" that is in A or B
in other words, if a box is "male" or if a box is "for", mark it.
How many boxes are marked ?

Answer 35

Three boxes are marked?

Answer 36

yes. now add up the votes in those 3 boxes. that represents A U B
divide by the total votes (20) to get the Pr( A U B)

Answer 37

3/5 or 0.6?

Answer 38

? what do the 3 boxes add up to ?

Answer 39

4+ 6+ 2 = 12

Answer 40

Is it wrong?

Answer 41

ok, yes that is correct

Answer 42

If you want to use a formula notice
Pr(A) = 10/20 and Pr(B)= 6/20
if we add them we get 16/20
*but we double counted* the box with 4 in it (male and for)
so we adjust by subtracting off the 4/20 which happens to be Pr(A \( \cap\) B)

so Pr(AUB)= Pr(A)+Pr(B) - Pr(A ∩ B)

Answer 43

Thank you so much!! You helped me understand this better than anyone textbook could!!