The probability of guessing the correct answer to a certain test questions is `x/(12)dot` If the probability of not guessing the correct answer to this question is `2/3dot` then x = 2 (b) 3 (c) 4 (d) 6

Options

A. 2
B. 3
C. 4
D. 6

Answer

C

Explanation

Given Probability of guessing a correct answer `= x/12`
and probability of not guessing the correct answer `= 2/3`
As we know
P(occurrence of an event) + P(non-occurrence of an event) = 1
`therefore x/12 + 2/3 = 1 rArr (x + 8)/(12) = 1 rArr x = 12-8 = 4`