Answer:
Mean score of the given data is 7.31.
Step-by-step explanation:
We are given that a true-false quiz with 10 questions was given to a statistics class.
Following is the probability distribution for the score of a randomly chosen student;
X P(X)
5 0.07 0.35
6 0.17 1.02
7 0.38 2.66
8 0.21 1.68
9 0.10 0.9
10 <u> 0.07 </u> 0.7
<u> </u><u> = 1 </u>
Firstly, it should be noted that the sum of probabilities, P(X) must be equal to 1.
Now, mean score is given by the following formula;
Mean, E(X) = {i.e. multiplying each score with the respective probability}
Mean, E(X) = 0.35 + 1.02 + 2.66 + 1.68 + 0.9 + 0.7
= 7.31
So, the mean score is <u>7.31.</u>
The interpretation of this score is that when the student takes a true-false quiz with 10 questions, he will on average is expected to get a score of 7.31.