Question

The probability of guessing the correct answer to certain question

is x/12

. If the probability of not guessing the correct answer to this

question 2/3



then x = ​

Answer 1

Answer:

Probability of guessing the correct answer to a certain test questions =

12

x

.

So, probability of not guessing the correct answer to a certain test questions =1−

12

x

But, 1−

12

x

=

3

2

.

⇒

12

x

=1−

3

2

⇒x=4.

Answer 2

Probability of guessing the correct answer to a certain test questions

$= \frac{x}{12}$

So, probability of not guessing the correct answer to a certain test questions

$= 1 - \frac{x}{12}$

but

$1 - \frac{x}{12} = \frac{2}{3}$

$= \frac{x}{12} = 1 - \frac{2}{3}$

$x = 4$