Pls help

[Annasilva]

When you leave a party hall, you can be subjected to an alcohol test as soon as you can check whether you are allowed to drive or not. However, the test is not 100% reliable: it only reacts positively on 94% of people who drink too much, and it also responds on 8% of people who do not drink too much. If you know that 40% of those present people drank too much during this evening, calculate the probability that he or she reacts negatively, if he or she drunk too much.

[Guest]

Imagine that 1000 people are tested. 40%, 400 people, drank too much, 1000- 400= 600 did not. Of the 400 who drank too much, 94%, 0.94(400)= 396, test positive, the other 400- 396= 4 do not. That is, of the 400 people who drank too much, 4, so 4/400= 1/100= 0.01 or 1% react negatively.