QUESTION 22 4 points S The lifetime of a particular type of battery is normally distributed...
The lifetime of a certain type of battery is normally distributed with mean value 10 hours (a) If a pack of 4 batteries is purchased, what is the probability that the average lifetime of the (b) How many batteries must be purchased such that the probability that their average lifetime is at and standard deviation 1 hour batteries in the package is at least 9 hours? least 9.5 hours is .99?
Problem 7: [5 points) The lifetime of a certain type of battery is normally distributed with a mean value of 10 hours and a standard deviation of 1 hour. There are 4 batteries in a package. Question: What lifetime value is such that the total lifetime of all batteries in a package say, X1 + X2 + X3 + X4, exceeds that value for only 2% of all packages?
15. A certain type of automobile battery is known to have a lifetime which is normally distributed with mean 1,200 days and standard deviation 90 days. For how many days should these batteries be guaranteed if the manufacturer wants to replace only 20% of the batteries sold because they "died" before the guarantee expired? A. 1052 B. 1105 C. 1124 D. 1094 16. A particular television commercial is understood by 30% of first graders and 65% of fourth graders....
1. Suppose that the length of time a particular type of battery lasts follows an exponential distribution with a mean of 25.0 days. Find the probability that the average time a sample of 49 batteries lasts is at most 24.7 days a. 0.4665 b. 0.3723 c. 0.6277 d. 0.5335 2. Suppose that the length of time a particular type of battery lasts follows an exponential distribution with a mean of 25.0 days. Suppose the length of time a battery lasts...
10.9 12.6 14.3 16 Question 8 1 pts The number of points on a particular test are normally distributed. The average number of points is 16: the standard deviation is 1.7 points. Use the empirical rule estimate the probability of the points being less than 12.6. Question4 For a school project, two students Shona and Miguel, recorded the number of text messages each of them sent each day for a 60-day period The box plots summarize the data Shona Miguel...