A manufacturer of computer screens has determined that the screens require servicing after a mean of 70 months, with a standard deviation of 8.8 months. What length of warranty should be offered, if the manufacturer wants to repair less than 0.5% of the screens under the warranty?
Standard deviation- please help!
- Thread starter jcooperxo
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Is the distribution of failures Normal? Symmetric? This information should be in the problem statement.
A warranty of 70 months will suggest that they repair half the failures.
A warranty of 70 months less 8.8 mos (61.2 mos) suggests about 16% will be repaired.
A warranty of 70 months less 2x8.8 mos (52.4 mos) suggests about 1½% will be repaired.
I'm just using the Empirical Rule. You should be more exact.
A warranty of 70 months will suggest that they repair half the failures.
A warranty of 70 months less 8.8 mos (61.2 mos) suggests about 16% will be repaired.
A warranty of 70 months less 2x8.8 mos (52.4 mos) suggests about 1½% will be repaired.
I'm just using the Empirical Rule. You should be more exact.
D
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You'll need to use z-distribution for this problem.
How can you use this in your problem? What does your class-notes say? what does your text-book say?
Please share your work/thoughts with us.
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