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An experimental surgical procedure is being studied as an alternative to the old method. Both methods are considered safe. Five surgeons perform the operation on two patients matched by age, sex, and other relevant factors, with the results shown. The time to complete the surgery (in minutes) is recorded.
Surgeon 1 Surgeon 2 Surgeon 3 Surgeon 4 Surgeon 5 Old way 37 51 25 41 55 New way 29 43 21 31 59 Click here for the Excel Data File (a-1)
Calculate the difference between the new and the old ways for the data given below. Use α = .010. (Negative values should be indicated by a minus sign.) X1 X2 X1 - X2 Surgeon Old Way New Way Difference 1 37 29 8 2 51 43 8 3 25 21 4 4 41 31 10 5 55 59
(a-2) Calculate the
Mean:
Standard Deviation:
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