XR14-80 Before deciding which of two types of stamping machine should be purchased, the plant…

XR14-80 Before deciding which of two types
of stamping machine should be purchased, the plant manager of an automotive
parts manufacturer wants to determine the number of units that each produces.
The two machines differ in cost, reliability and productivity. The firm’s
accountant has calculated that machine A must produce 25 more non-defective
units per hour than machine B to warrant buying machine A. To help decide, both
machines were operated for 24 hours. The total number of units and the number
of non-defective units produced by each machine per hour were recorded. These
data are
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XR14-80 Before deciding which of two types
of stamping machine should be purchased, the plant manager of an automotive
parts manufacturer wants to determine the number of units that each produces.
The two machines differ in cost, reliability and productivity. The firm’s
accountant has calculated that machine A must produce 25 more non-defective
units per hour than machine B to warrant buying machine A. To help decide, both
machines were operated for 24 hours. The total number of units and the number
of non-defective units produced by each machine per hour were recorded. These
data are recorded in the following way: column 1 = total number of units
produced by machine A; column 2 = number of defectives produced by machine A;
column 3 = total number of units produced by machine B; column 4 = number of
defectives produced by machine B. Determine which machine should be purchased.
(Use a 5% significance level.)

Q922;

XR14-81 How important to your health are
regular holidays? In a study, a random sample of men and women were asked how
frequently they take holidays. The men and women were divided into two groups
each. The members of group 1 had suffered a heart attack; the members of group
2 had not. The number of days of holiday last year was recorded for each person.
Can we infer that men and women who suffer heart attacks take fewer holidays
than those who did not suffer heart attacks?

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