Bad gums may mean a bad heart. Researchers discovered that 75% of people who have suffered a heart attack had periodontal disease, an inflammation of the gums. Only 27% of healthy people have this disease. Suppose that in a certain community heart attacks are quite rare, occurring with only 11% probability.
A. If someone has periodontal disease, what is the probability that he or she will have a heart attack?
Probability =
B. If 43% of the people in a community will have a heart attack, what is the probability that a person with periodontal disease will have a heart attack?
Probability =
Bad gums may mean a bad heart. Researchers discovered that 75% of people who have suffered a heart attack had?
2010-06-25 2:08 am
回答 (4)
2010-06-25 5:12 am
✔ 最佳答案
this is a problem in conditional probabilityD = have periodontal disease
H = have suffered heart attack
qA
P(H) = 11%
P(H & D) = 75% * 11% = 8.25%
P(H' & D) = 27% * 89% = 24.03%
P(D) = sum of the above = 32.28%
P(H | D) = P(H & D) / P(D)
= 8.25/32.28
= .2556 or 25.56%
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qB
just change 11% to 43% & calculate as above
P(H) = 43%
P(H & D) = 75% * 43% = 32.25%
P(H' & D) = 27% * 57% = 15.39%
P(D) = sum of the above = 47.64%
P(H | D) = P(H & D) / P(D)
= 32.25/47.64
= .677 or 67.7%
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2016-09-14 9:18 am
possible yes
2016-08-06 4:08 pm
I love this question
2010-06-25 2:21 am
A) .11*.27= .0297
= 2.97%
B) .43*.27= .1161
= 11.61%
= 2.97%
B) .43*.27= .1161
= 11.61%
收錄日期: 2021-05-01 13:15:35
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