SOLUTION: A manufacturer knows that their items have a normally distributed lifespan, with a mean of 8.9 years, and standard deviation of 1.5 years. If you randomly purchase one item, wha

Algebra ->  Test -> SOLUTION: A manufacturer knows that their items have a normally distributed lifespan, with a mean of 8.9 years, and standard deviation of 1.5 years. If you randomly purchase one item, wha      Log On


   



Question 1179345: A manufacturer knows that their items have a normally distributed lifespan, with a mean of 8.9 years, and standard deviation of 1.5 years.
If you randomly purchase one item, what is the probability it will last longer than 13 years?

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!

Hi
Distribution: normal with µ = 8.9yr and σ = 1.5yr
randomly purchase one item:
Continuous Curve:
Using TI or similarly an inexpensive calculator like an Casio fx-115 ES plus

P( x >  13) = normalcdf(13, 9999,8.9,1.5) = .0031 
Or
P( x >  13) = 1 - P( x ≤ 13) = 1 - 0.9969 = .0031
Wish You the Best in your Studies.