contestada

You arrive in your history class today only to discover there is a pop quiz! You haven't studied and you aren't at all prepared. Fortunately, the quiz is multiple choice. Each question has five answer choices. You happen to have a die in your pocket. For each question you roll the die and answer A if the die shows 1, B if the die shows 2, etc, leaving the question blank if the die shows a six. For each question you are given one point if you answer it correctly and lose 1/4 point if you answer it incorrectly. You aren't penalized if you leave it blank, you just don't earn a point. What is the expected value for points earned on each question? Enter your answer as a decimal, rounded to two decimal places if necessary

Respuesta :

The probability of getting a right answer is 1/6, with a value of 1.

The probability of getting a wrong answer is 4/6 with, a value of -1/4.

The probability of leaving a question empty is 1/6, with a value 0.

The Expected value is 

[tex]1* \frac{1}{6}+( -\frac{1}{4} )* \frac{1}{6}+( -\frac{1}{4} )* \frac{1}{6}+( -\frac{1}{4} )* \frac{1}{6}+( -\frac{1}{4} )* \frac{1}{6}+0* \frac{1}{6}[/tex]

[tex]= \frac{1}{6} +4( -\frac{1}{4} )* \frac{1}{6}=\frac{1}{6}-\frac{1}{6}=0[/tex]

Otras preguntas