1. ## Probability puzzle

If you choose an answer to this question at random what is the chance you will be correct?

A) 25%

B) 50%

C) 60%

D) 25%

2. ## Re: Probability puzzle

Spoiler:
Pr[choose any letter] = 1/4

Pr[Correct]=(Pr[Correct|choose a]+Pr[Correct|choose b] + Pr[Correct | choose c] + Pr[Correct | choose d]) x 1/4

Pr[Correct] = (1/2 + 1/4 + 1/4 + 1/2) x 1/4 = 3/2 x 1/4 = 3/8

Pr[Correct] = 3/8