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Test standby time and compare significance statements
A random sample of 90 mobile-phone batteries has standby times hours summarized by and . Test at 1% whether the population mean standby time is less than 36.0 hours.
The same type is advertised as having talk-time 5 hours. A separate test at 5% finds significant evidence that population mean talk-time is less than 5 hours. Using only that information, classify each statement as necessarily true, necessarily false, or neither, giving reasons:
(a) There is significant evidence at 10% that the population mean talk-time is less than 5 hours.
(b) There is significant evidence at 5% that the population mean talk-time is not 5 hours.
[N2001/II/10]
CJC · Discussion · Question 4
Separate the standby and talk-time tests, and double a one-sided p-value only for the corresponding symmetric two-sided test.