Question

The data represent the results for a test for a certain disease. Assume one individual from the group is randomly selected. Find the probability of getting someone who tests positive, given that he or she had the disease.

The individual actually had the disease.
Yes No
Positive 141 6
Negative 11 142
@jim_thompson5910 I thought that I was done. Look this one. lol!! I am not sure what I am doing wrong!! Please help me!!

Thanks!

Answer 1

key phrase: given that he or she had the disease

Answer 2

so we know for a fact that this person has the disease

Answer 3

how many people total have the disease?

Answer 4

It's not suppose to be 141+6= 147. Like the one before?

Answer 5

no

Answer 6

that's the total who tested positive

Answer 7

how many actually have the disease?

Answer 8

ooh, 300

Answer 9

no

Answer 10

got it

152

Answer 11

the first column has a "yes" under "The individual ACTUALLY had the disease"

Answer 12

so the first column represent everyone who actually has the disease

Answer 13

I got it... Oh boyy!!

Answer 14

I am getting it now.. I was confused reading this.!! I got the answer.

Answer 15

P(141/152)=0.9276=0.928 =D

Answer 16

that's correct, but the notation is a bit off


P(test positive | has disease) = (# of people who test positive and have disease)/(# of people who have disease)


P(test positive | has disease) = 141/152

Answer 17

The vertical bar | means "given"

Answer 18

I understand now.. Yes I did it that way to round it!! But I am clear now...
Thanks again for your help!! :*

Answer 19

np