In: Statistics and Probability
Treatment of wastewater is important to reduce the concentration of undesirable pollutants. One such substance is benzene which used as industrial solvent. Two methods of water treatment are being compared. Treatment 1 is applied to 5 specimens of wastewater while Treatment 2 is applied to 7 specimens. The benzene concentrations in milligrams per liter are as follows:
Treatment 1 | Treatment 2 |
x-bar: 6.8 mg/L | x-bar: 5.7 mg/L |
s1 = 0.9 mg/L | s2 = 1.6 mg/L |
n1 = 5 | n2 = 7 |
A) Select the correct assumptions.
Both samples are greater than 30.
The two samples are independent.
Both standard deviations are unknown and we do not assume that they are equal.
Both samples are simple random samples.
We assume that the standard deviations of both samples are equal.
B) State the null and alternative hypotheses.
C) State the p-value to 4 decimal places or the critical value to 3 decimal places.
D) State the conclusion addressing the original claim, in context.