Question

1. The mean age at CNM is 26.2 years old. The table contains a random sample of classroom data from a General Chemistry II class.

Student Number	Gender (M = male; F = female; O = other)	Race (Y = Latinx; N = Other)	Age (18 years or older)	GPA (0-4 point scale)
1	M	Y	22	2.4
2	O	Y	20	3.5
3	F	Y	22	2.8
4	M	Y	28	2.8
5	F	Y	30	4.0
6	M	Y	23	3.8
7	M	N	18	3.2
8	F	N	20	3.5
9	O	N	18	2.8
10	M	N	20	4.0

1. 1. Use the space or the graph paper below to make a dot plot or a box plot (your choice) for Age.
2. 2. What is the sample mean for Age in this dataset?
3. 3. What is the sample standard deviation for Age in this dataset?
4. 4. How many degrees of freedom are there?
5. 5. Perform a hypotesis test for Age in this dataset. What is your conclusion?

Answer 1

1. The dotplot is:

2. The sample mean = 22.1

3. The sample standard deviation for Age = 4.01

4. df = 10 - 1 = 9

5. The hypothesis being tested is:

H₀: µ = 26.2

H_a: µ ≠ 26.2

26.200	hypothesized value
22.100	mean Age
4.012	std. dev.
1.269	std. error
10	n
9	df
-3.231	t
.0103	p-value (two-tailed)

The p-value is 0.0103.

Since the p-value (0.0103) is less than the significance level (0.05), we can reject the null hypothesis.

Therefore, we can conclude that µ ≠ 26.2.