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Vikentia [17]
2 years ago
8

On a quiz there are four multiple-choice questions worth 3 points each and two true/false questionsworth 1 point each . Each mul

tiple-choice question has five possible choices . If a student randomlyguesses on each question , what is the expected value of the student's score on the test ?
Mathematics
1 answer:
Anastaziya [24]2 years ago
7 0

Answer:

The expected value of the student's score on the test is 3.4.

Step-by-step explanation:

Multiple choice questions:

worth 3 points.

Five possible choices, one of which is correct. So the expected value of the student in each multiple choice question is:

m = 3\frac{1}{5} = 0.6

True/false questions:

worth 1 point.

2 options, one of which is correct, so the expected value for each is:

t = 1\frac{1}{2} = 0.5

What is the expected value of the student's score on the test ?

4 multiple choice, two true-false. So

E = 4m + 2f = 4(0.6) + 2(0.5) = 2.4 + 1 = 3.4

The expected value of the student's score on the test is 3.4.

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