This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: least two years (730 days) without trouble? P( X 730 ) =  100 3 6 730 Z P = P( Z 1.00 ) = 1 ( 1.00 ) = 1 0.8413 = 0.1587 . c) (4) A cleaning service purchased (a random sample of) 8 vacuum cleaners. Find the probability that the average duration of troublefree operation of those 8 vacuum cleaners will be at least two years (730 days). = 630, = 100, n = 8. Need P( X 730 ) = ? Since the population we sample from is normal, . n Z X = P( X 730 ) =  8 100 30 6 30 7 Z P = P( Z 2.83 ) = 1 ( 2.83 ) = 1 0.9977 = 0.0023 ....
View Full
Document
 Spring '08
 Kim
 Statistics, Probability

Click to edit the document details