Statistics Sum Solution (***** 100% Correct answer + Calculation all sum *****)1) If light bulbs have lives that are normally distributed with a mean of 2500 hours and a standard deviation of 500 hours what percentage of light bulbs have a life less than 2500 hours?2)The lifetimes of light bulbs of a particular type are normally distributed with a mean of 370 hours and a standard deviation of 5 hours. What percentage of bulbs has lifetimes that lie within 1 standard deviation of the mean on either side3) The amount of Jen s monthly phone bill is normally distributed with a mean of $60 and a standard deviation of $12. Fill in the blanks:68% of her phone bills are between $______________ and $______________.4)The amount of Jen s monthly phone bill is normally distributed with a mean of $50 and a standard deviation of $10. Find the 25thpercentile.5) The diameters of bolts produced by a certain machine are normally distributed with a mean of 0.30 inches and a standard deviation of 0.01 inches. What percentage of bolts will have a diameter greater than 0.32 inches?6)The annual precipitation amounts in a certain mountain range are normally distributed with a mean of 88 inches and a standard deviation of 10 inches. What is the likelihood that the mean annual precipitation during 25 randomly picked years will be less than 90.8 inches? 7) A final exam in Statistics has a mean of 73 with a standard deviation of 7.73. Assume that a random sample of 24 students is selected and the mean test score of the sample is computed. What percentage of sample means are less than 708) A mean score on a standardized test is 50 with a standard deviation of 10. Answer the followingChapter Six:1) For the following questions would the following be considered significant if its probability is less than or equal to 0.05? 2.Assume that a study of 500 randomly selected school bus routes showed that 480 arrived on time. Is it significant for a school bus to arrive late?2) If you flip a coin three times the possible outcomes are HHH HHT HTH HTT THH THT TTH and TTT. What is the probability of getting at least one head3) A sample space consists of 64 separate events that are equally likely. What is the probability of each? 4) A bag contains 4 red marbles 3 blue marbles and 7 green marbles. If a marble is randomly selected from the bag what is the probability that it is blue5) The data set represents the income levels of the members of a country club. Estimate the probability that a randomly selected member earns at least $98000.112000 126000 90000 133000 94000112000 98000 82000 147000 18200086000 105000 140000 94000 126000119000 98000 154000 78000 1190006) Suppose you have an extremely unfair coin: The probability of a head is and the probability of a tail is . If you toss the coin 32 times how many heads do you expect to see7) The following table is from the Social Security Actuarial Tables. For each age it gives the probability of death within one year the number of living out of an original 100000 and the additional life expectancy for a person of that age. Determine the following using the table:

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