Probabilities are used to determine the chances of an event
- The probability that a person is sick is: 0.008
- The probability that a test is positive, given that the person is sick is 0.9833
- The probability that a test is negative, given that the person is not sick is: 0.9899
- The probability that a person is sick, given that the test is positive is: 0.4403
- The probability that a person is not sick, given that the test is negative is: 0.9998
- A 99% accurate test is a correct test
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<u>(a) Probability that a person is sick</u>
From the table, we have:

So, the probability that a person is sick is:

This gives


The probability that a person is sick is: 0.008
<u>(b) Probability that a test is positive, given that the person is sick</u>
From the table, we have:

So, the probability that a test is positive, given that the person is sick is:

This gives


The probability that a test is positive, given that the person is sick is 0.9833
<u>(c) Probability that a test is negative, given that the person is not sick</u>
From the table, we have:


So, the probability that a test is negative, given that the person is not sick is:

This gives


The probability that a test is negative, given that the person is not sick is: 0.9899
<u>(d) Probability that a person is sick, given that the test is positive</u>
From the table, we have:


So, the probability that a person is sick, given that the test is positive is:

This gives


The probability that a person is sick, given that the test is positive is: 0.4403
<u>(e) Probability that a person is not sick, given that the test is negative</u>
From the table, we have:


So, the probability that a person is not sick, given that the test is negative is:

This gives


The probability that a person is not sick, given that the test is negative is: 0.9998
<u>(f) When a test is 99% accurate</u>
The accuracy of test is the measure of its sensitivity, prevalence and specificity.
So, when a test is said to be 99% accurate, it means that the test is correct, and the result is usable; irrespective of whether the result is positive or negative.
Read more about probabilities at:
brainly.com/question/11234923