In a multiple choice quiz there are 5 questions and 4 choices for each question (a, b, c, d). Robin has not studied for the quiz at all, and decides to randomly guess the answers. What is the probability that

Respuesta :

Answer:

[tex]Pr = 0.140625[/tex]

Step-by-step explanation:

Given

[tex]n = 5[/tex] --- questions

[tex]options = 4[/tex] ---- a, b, c or d

Required

The probability that 1st correct question is the 3rd

The probability of selecting the right answer is:

[tex]p = \frac{1}{options}[/tex]

[tex]p = \frac{1}{4}[/tex]

[tex]p = 0.25[/tex]

Using complements, we have:

[tex]q = 1-p[/tex]

[tex]q = 1-0.25[/tex]

[tex]q = 0.75[/tex] --- probability of selecting the wrong answer

The required probability is represented as:

Pr = First is wrong * Second is wrong * Third is correct

[tex]Pr = q * q * p[/tex]

This gives

[tex]Pr = 0.75 * 0.75 * 0.25[/tex]

[tex]Pr = 0.140625[/tex]