TABLE 7-3 The Lifetimes of a Certain Brand of Light Bulbs Are

question 118

Essay

TABLE 7-3
The lifetimes of a certain brand of light bulbs are known to be normally distributed with a mean of 1,600 hours and a standard deviation of 400 hours. A random sample of 64 of these light bulbs is taken.
-Referring to Table 7-3, the probability is 0.20 that the sample mean lifetime differs from the population mean lifetime by at least how many hours?

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Definitions:

Pubic Hair

Hair that grows on the genital area after reaching puberty, serving as a sign of sexual maturity and helping to reduce friction.

Klinefelter Syndrome

A genetic condition affecting males, characterized by an extra X chromosome, leading to symptoms like reduced muscle mass, reduced facial and body hair, and infertility.

XXY

A chromosomal condition in which a male has an extra Y chromosome, often associated with Klinefelter syndrome.

Turner Syndrome

A chromosomal disorder affecting females, characterized by the absence of part or all of a second sex chromosome, leading to various developmental issues.