Question

Here is a link to the data set collected by Dr. Hernandez. Her research team has a data set of the weight of fishes caught from both the contaminated lake and the pristine lake. Assume both of these data sets have equal variance.

1.) Perform the correct statistical test and determine the P value to test Dr. Hernandez's hypothesis. Report your answer for P rounded to four decimal places.

Fish Weight (g)
Pristine	Contaminated
45.3	79.3
56.8	96.8
79.6	84.6
61.4	79.6
39.6	97.6
89.3	80.5
74.9	76.9
95.5	89.7
71.6	86.6
92	89.4
76.3	72.5
46.5	92.3
77.6	68.9
88.7	56.9
70.6	99.5
55.4	87.3
90.3	84
77.6	88.5
54.6	79
39.9	71.2
90.5	78.8
84.6	68.8
68.8	61.6
82.9	98.5
85.2	58.4
90.5	91.1
86.34	97.6
79.9	71.4
86.7	89.6
56	81.7

Answer 1

Here we need to compare mean of two independent samples. So we need to use independent sample t test. Hypotheses are:

Following is the output generated by excel:

Decision: Since p-value is less than 0.05 so we reject the null hypothesis.

Conclusion: There is sufficient evidence to conclude that weight of fishes are significantly differ from each other.