Question

binge drinker male = 0.11 female = 0.12
not a binge drinker male = 0.32 female = 0.45

what is the probability that a randomly selected male student is not a binge drinker?
Is this a complement problem? P (A) + P (not A) = 1? and so P (male is a binge drinker : 0.11) + P (male is not a binge drinker: 0.32) = 0.11+ 0.32 = .43 and 1 - .43 = .57 ?

Answer 1

P(not a binge drinker| male) = P(not a binge drinker AND male)/P(male)

P(not a binge drinker| male) = 0.32/(0.11+0.32)

P(not a binge drinker| male) = 0.74418604651162

Answer 2

so, it is not a complement problem...I am not familiar with your method...what rule are you using please? I don't get probability at all! thanks for your kind response

Answer 3

here's one way to think of it

Answer 4

let's say there are 100 people total

Answer 5

11 of them would be male binge drinkers

notice how 11/100 = 0.11, so that fits with the probability

Answer 6

32 males would not be binge drinkers

32/100 = 0.32, so that fits too

Answer 7

12 females would be binge drinkers

12/100 =0.12

Answer 8

45 females would not be binge drinkers

Answer 9

and 45/100 = 0.45

so it all fits

Answer 10

how many males are there total (in this pool of 100 people)?

Answer 11

total males in group = 43

Answer 12

good

Answer 13

sorry, how many males are NOT binge drinkers (of the 100)

Answer 14

0.32 or 32/100 are not BD

Answer 15

there are 32 males who do not binge drink

so because there are 43 males total, the probability is

32/43 = 0.74418604651162

Answer 16

we are only focusing on the males because it specifically states that you chose a male

Answer 17

I did understand that part but was trying to find a rule that fit the question...I never really grasped the whole chapter on probabilities...and the class is moving too fast.. thanks for explaining...

Answer 18

well it's using bayes theorem

but I think it's better to think of it in this way

Answer 19

never heard of bayes theorem...test tonight over the whole semester...hopefully he will have only 1-2 probability questions...and not the hard ones :) not that it might not be interesting to understand probabilities better...but my brain doesn't work like that....I envy people who really get math..

Answer 20

this isn't a probability course?

Answer 21

No, its an intro to the practice of statistics...a crunched down, short version just for nurses going on for Master's....this whole class has shaken my confidence ....I am an A student but not in this class...I think I could get it better if we had the whole semester instead of just a few weeks...

Answer 22

i hate classes that are supposed to be 5 months but are jammed in like 3 weeks

Answer 23

but I'm sure you'll make it

Answer 24

yes, it didn't help that the instructor is short-tempered, easily frustrated when I ask him to clarify something...and there is no math lab/no tutors available...it has been the most miserable experience...but tonight is it...I'll pass, even if not with a better grade...I could take it again elsewhere and see what happens...uuhhh..Did I I really say that....Yikes! Thanks again for sharing your knowledge...

Answer 25

I'm sure you'll be fine. You just need confidence. You're welcome