The relationship between high blood pressure and cigarettes - data is as follows:
Non-smokers moderate heavy total
High blood pressure 21 36 30 87
normal blood press. 48 26 19 93
totals 69 62 49 180
If you randomly pick one of the test subjects, what is prob. that:
a- they have high blood pressure
b - they are non smokers
c - they are a non smoker who happens to have high blood pressure
d - they have high blood pressure and (given) are a heavy smoker
e - they are a non smoker, (given) ther person is experiencing high blood pressure symptoms
So, here is what I cannot understand in the problem:
I recall reading that the probability of an event is the number of ways an event can occur, divided by the number of all possible outcomes.
So, example: Say you have 5 marbles in a container, 2 reds, 3 greens, what is the probability of selecting a red marble at random?
Well, that is 2/5, since there are 2 ways you can get a red marble (select either of the 2 red marbles) then divide by the total number of possible outcomes (there are a total of 5 marbles to choose from).
So here we are given a number of people (is this the possible outcomes?) and we want to find the probability of "some event" (I think that is the subject have high blood pressure, are non-smokers, and are nonsmokers who have high blood pressure, respectively -right?)
How do you proceed?
Non-smokers moderate heavy total
High blood pressure 21 36 30 87
normal blood press. 48 26 19 93
totals 69 62 49 180
If you randomly pick one of the test subjects, what is prob. that:
a- they have high blood pressure
b - they are non smokers
c - they are a non smoker who happens to have high blood pressure
d - they have high blood pressure and (given) are a heavy smoker
e - they are a non smoker, (given) ther person is experiencing high blood pressure symptoms
So, here is what I cannot understand in the problem:
I recall reading that the probability of an event is the number of ways an event can occur, divided by the number of all possible outcomes.
So, example: Say you have 5 marbles in a container, 2 reds, 3 greens, what is the probability of selecting a red marble at random?
Well, that is 2/5, since there are 2 ways you can get a red marble (select either of the 2 red marbles) then divide by the total number of possible outcomes (there are a total of 5 marbles to choose from).
So here we are given a number of people (is this the possible outcomes?) and we want to find the probability of "some event" (I think that is the subject have high blood pressure, are non-smokers, and are nonsmokers who have high blood pressure, respectively -right?)
How do you proceed?