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Question
If P(E) = 0.05, what is the probability of ‘not E’?
Solution 1
We know that,
`P(barE) = 1- P(E)`
`P(barE) = 1 - 0.05`
`P(barE) =0.95`
Therefore, the probability of ‘not E’ is 0.95.
Solution 2
We know that,
P(E) + P(not E) = 1
Given, P(E) = 0.05
∴ P(not E) = 1 – P(E)
Or, P(not E) = 1 – 0.05
So, the probability of ‘not E’ is 0.95.
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