Question

Exercise 6. Bacterial level. A researcher studied the amount of bacteria in a hospital to see if there is a difference between carpeted and uncarpeted rooms. Air from each room tested was pumped over a Petri dish at a rate of 1 cubic foot per hour. The bacteria levels were measured. The results in bacteria per cubic foot are listed in the table below. At α = 0.05, can you support the claim that bacteria level in carpeted rooms is different that the level in rooms that are uncarpeted? Carpeted 11.8 8.2 7.1 13.0 10.8 10.1 14.6 14.0 12.8 9.6 Uncarpeted 12.1 8.3 3.8 7.2 12.0 11.1 10.1 13.7 8.8 9.3

Answer 1

t-Test: Two-Sample Assuming Unequal Variances
	Carpeted	Uncarpeted
Mean	11.2	9.64
Variance	6.144444	8.124888889
Observations	10	10
Hypothesized Mean Difference	0
df	18
t Stat	1.305939
P(T<=t) one-tail	0.104009
t Critical one-tail	1.734064
P(T<=t) two-tail	0.208018
t Critical two-tail	2.100922

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Test stats (t)= 1.305939

P-value = 0.208018

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P-value is greater than 0.05, Fail to reject Ho.

we have enough evidence against the calim to conclude that the means are not different