Answer to Question #178244 in Statistics and Probability for Roy Teodoro

Question #178244

a manufacturer of light bulbs produces bulbs that last a mean of 950 hours with a standard deviation of 12 hours what is the probability that the mean lifetime of the random sample of 10 of these bulbs is less than 90 hours


1
Expert's answer
2021-04-15T06:57:38-0400

let X a random variable showing the life of an incandescent lamp in hours \text{let X a random variable showing the life of an incandescent lamp in hours }

μ=950;σ=\mu= 950;\sigma= 12

XN(μ,σ2/n)X∼N(μ,σ^2/n)

Z=Xμσ/nZ= \frac{X-\mu}{\sigma/\sqrt{n}}

P(X<90)=P(Z<9095012/10)=P(Z<226)=0P(X<90)=P(Z<\frac{90-950}{12/\sqrt{10}})=P(Z<-226)=0

Answer: 0 is probability that the mean lifetime of the random sample of 10 of these bulbs is less than 90 hours



Need a fast expert's response?

Submit order

and get a quick answer at the best price

for any assignment or question with DETAILED EXPLANATIONS!

Comments

No comments. Be the first!

Leave a comment