A researcher wants to know the lifetime of a "BL" brand lamp. For necessity research, it takes 9 pieceso lamps to be tested. Experimental results shows an average lifetime of 1,500 hours with a standard Е (X); (æc) average lamp life deviation of 111 hours. Count it variance X and standard deviation under test.

A researcher wants to know the lifetime of a "BL" brand lamp. For necessity research, it takes 9 pieceso lamps to be tested. Experimental results shows an average lifetime of 1,500 hours with a standard Е (X); (æc) average lamp life deviation of 111 hours. Count it variance X and standard deviation under test.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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