Question

The probability of guessing the correct answer to a certain test question is x by 12
if the probability of not guessing the correct answer to this question is 2 by 3 then x equals

Answer 1

Answer:-

P(c) = x/12

P(c') = 2/3

We know that sum of the probability of an event happening and not happening is 1.

Hence, P(c) + P(c') = 1 or

x/12 + 2/3 = 1

x/12 = 1 - 2/3

x/12 = 1/3

3x = 12

x = 12/3

x = 4