The following data (in Drink ) represent the amount of soft drink filled in a sample of 50 consecutive 2-liter bottles. The results, listed horizontally in the order of being filled, were:
2.109 2.086 2.066 2.075 2.065 2.057 2.052 2.044
2.036 2.038 2.031 2.029 2.025 2.029 2.023 2.020
2.015 2.014 2.013 2.014 2.012 2.012 2.012 2.010
2.005 2.003 1.999 1.996 1.997 1.992 1.994 1.986
1.984 1.981 1.973 1.975 1.971 1.969 1.966 1.967
1.963 1.957 1.951 1.951 1.947 1.941 1.941 1.938
1.908 1.894
a. At the 0.05 level of significance, is there evidence that the mean amount of soft drink filled is different from 2.0 liters?
b. Determine the p-value in (a) and interpret its meaning.
c. In (a), you assumed that the distribution of the amount of soft drink filled was normally distributed. Evaluate this assumption by constructing a boxplot or a normal probability plot.
d. Do you think that the assumption needed in order to conduct the t test in (a) is valid? Explain.
e. Examine the values of the 50 bottles in their sequential order, as given in the problem. Does there appear to be a pattern to the results? If so, what impact might this pattern have on the validity of the results in (a)?
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