A soft-drink firm is evaluating an investment in a new type of canning machine. The company has already determined that it will be able to fill more cans per day for the same cost if the new machines are installed. However, it must determine the variability from the new machines to be equal to or smaller than that currently obtained using the old machines. A study is designed in which random samples of 40 cans are selected from the output of both types of machines and the amount of fill (in ounces) is determined. The data are given below.
OLD MACHINES
16.74 15.75 16.19 16.54 15.92 16.29 16.44 16.29
16.38 16.47 16.56 16.42 16.08 16.47 16.02 16.74
15.97 16.47 16.06 16.64 16.4 16.4 16.28 16.66
16.8 16.36 16.36 16.27 16.43 16.26 16.31 16.59
16.24 16.63 16.15 16.17 16.32 16.81 16.27 17.09
NEW MACHINES
15.64 15.81 16.2 16.36 16.36 16.05 16.07 16.04
16.08 16.31 16.5 16.14 16.12 16.3 16.41 16.11
16.2 16.29 15.75 16.22 16.12 16.23 16.19 16.59
16.08 16.07 16.15 16.5 16.25 16.25 16.19 16.13
15.96 16.02 16.29 15.99 15.99 16.42 16.15 16.23
a.) Estimate the standard deviations in fill for types of machines using 95% confidence intervals.
