Question

. Consider the following scores on a final exam.

Emma	85
Noah	90
Olivia	95
Mason	87
Liam	88
Sophia	94
Isabella	92
Ethan	95
James	92
Charlotte	91

3a. What is the mean test score?

3b. What is the standard deviation of the test scores?

3c. Compare the standard deviation and coefficient of variance from the Mid-Term Exam (problem 2) to the standard deviation and coefficient of variance from the Final Exam. What does this tell you about the scores on the mid-term compared to the final?

Answer 1

(3a) Mean test score () is given by:

$ar{x}=rac{sum_{i=1}^{10}x_{i}}{10}=rac{909}{10}=90.9$

So,

Answer is:

90.9

(3b)

x	(x - )	(x - )2
85	- 5.9	34.81
90	- 0.9	0.81
95	4.1	16.81
87	- 3.9	15.21
88	- 2.9	8.41
94	3.1	9.61
92	1.1	1.21
95	4.1	16.81
92	1.1	1.21
91	0.1	0.01
total =		104.9

Standard deviation (s) is given by:

So,

Answer is:

3.4140

(3c)

For Final Exam:

Standard deviation = 3.4140

Coefficient of Variation (CV) is given by:

%

Since the details of Mid Term Exam are not provided, comparison cannot be made.