##
The reliability of a COVID PCR test is specified as follows:

Of people having COVID, 90% of the test detects the disease but 10% goes undetected. Of people free of COVID, 99% of the test is judged COVID negative but 1% are diagnosed as showing COVID positive. From a large population of which only 0.1% have COVID, one person is selected at random, given the COVID PCR test, and the pathologist reports him/her as COVID positive.

Based on the above information, answer the following:

##
**
Question 1
**

## What is the probability of the ‘person to be tested as COVID positive’ given that ‘he is actually having COVID?

## (a) 0.001

## (b) 0.1

## (c) 0.8

## (d) 0.9

##
**
Question 2
**

## What is the probability of the ‘person to be tested as COVID positive’ given that ‘he is actually not having COVID’?

## (a) 0.01

## (b) 0.99

## (c) 0.1

## (d) 0.001

##
**
Question 3
**

## What is the probability that the ‘person is actually not having COVID?

## (a) 0.998

## (b) 0.999

## (c) 0.001

## (d) 0.111

##
**
Question 4
**

## What is the probability that the ‘person is actually having COVID given that ‘he is tested as COVID positive’?

## (a) 0.83

## (b) 0.0803

## (c) 0.083

## (d) 0.089

##
**
Question 5
**

## What is the probability that the ‘person selected will be diagnosed as COVID positive’?

## (a) 0.1089

## (b) 0.01089

## (c) 0.0189

## (d) 0.189

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