A PC Company Uses Two Suppliers for Rechargeable Batteries for Its

question 55

Essay

A PC company uses two suppliers for rechargeable batteries for its notebook computers.Two factors are important quality features of the batteries: mean use time and variation.It is desirable that the mean use time be high and the variability be low.Recently,the PC maker conducted a test on batteries from the two suppliers.In the test,9 randomly selected batteries from Supplier 1 were tested and 12 randomly selected batteries from Supplier 2 were tested.The following results were observed:
Supplier 1 Supplier 2
n₁ = 9 n₂ = 12 ₁ = 67.25 min ₂ = 72.4 min
_s1 = 11.2 min s₂ = 9.9 min
Based on these sample results,can the PC maker conclude that a difference exists between the two batteries with respect to the population standard deviations? Test using a 0.10 level of significance.

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Definitions:

Ordinary Memories

Refer to the typical or everyday recollections that individuals have about their past experiences.

Phi Effect

An optical illusion of perceived motion created when stationary objects—shown in sequence—are viewed rapidly one after another.

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Individuals who doubt their accomplishments and fear being exposed as a "fraud," despite evidence of their competence.

EEG

Electroencephalography, a method to record electrical activity of the brain via electrodes placed on the scalp.