ney4r2hieWhita ney4r2hieWhita

26-11-2016
Mathematics

Answered

A company installs 5000 light bulbs, each with an average life of 500 hours, standard deviation of 100 hours, and distribution approximated by a normal curve. Find the percentage of bulbs that can be expected to last the period of time. Less than 690 hours

A97.06%

B47.14%

C97.1%

D97.2%

Verified Answer :

nobillionaireNobley nobillionaireNobley

29-11-2016

Let X be a random variable representing the number of hours a bulb is expected to last.
P(X < 690) = P(z < (690 - 500)/100) = P(z < 190/100) = P(z < 1.9) = 0.97128 = 97.1%

Answer Link

Related Questions

What did Hatshepsut do as pharaoh of Egypt

In Ernest Hemingways short story In Another Country why does the narrator see himself as different from the other wounded soldiers who visit the hospital 1 poin

Jenna is reviewing her friend Tammys paper She notices that Tammys grammar is incorrect in several places What is a constructive way for Jenna to give feedback

In the early 1800s society considered temperance to be a respectable cause for female reformers because this issue related to

Keplers 1st Law states that A planets move in a circular path B planets move in elliptical paths C planets move at a constant speed D a planets orbital radius i

what is homeostasis like

QuestionHigh voltages carry electricity for longdistance transmission What areused to lower that voltage for distribution and usage

Hemophilia is a condition where the blood clotting action is dangerously high True False A female can be susceptible to expressing hemophilia True False What wo

Paul has a collection of 36 marbles He separated the marbles into 3 equal groups to share with his friends but he decided to keep 23 of the marbles for himself

Explain how the specific heat of water helps keep our bodies from overheating

Web Analytics