68. A manufacturer knows that their items have a normally distributed lifespan, with a mean of 12 years, and standard deviation of 1.4 years. The 4% of items with the shortest lifespan will last less than how many years? (show all work) |

A manufacturer knows that their items have a normally distributed lifespan, with a mean of 7.1 years, and standard deviation of 2.2 years. The 8% of items with the shortest lifespan will last less than how many years? Please show your answer to one decimal place. # of years =

Use the formula to find the standard error of the distribution of differences in sample means, x¯1-x¯2.Samples of size 115 from Population 1 with mean 94 and standard deviation 14 and samples of size 85 from Population 2 with mean 75 and standard deviation 17Round your answer for the standard error to two decimal places.standard error = Enter your answer in accordance to the question statement

A local health care facility would like to estimate the proportion of patients referred to them by the local hospital.  What size sample would be required to estimate the population proportion of hospital referrals within 0.08 at the 98% confidence level?    a) What is the z-value?    b) What is the margin of error?    c) What is the sample size, n?

The time spent​ (in days) waiting for a heart transplant in two states for patients with type A+ blood can be approximated by a normal​ distribution, as shown in the graph to the right. Complete parts​ (a) and​ (b) below. u= 134 0=18.1 What is the shortest time spent waiting for a heart that would still place a patient in the top 30​% of waiting​ times?