The lengths of pregnancies in a small rural village are normally distributed with a mean of 269 days and a standard deviation of 12 days. In what range would you expect to find the middle 50% of most pregnancies? Between and If you were to draw samples of size 30 from this population, in what range would you expect to find the middle 50% of most averages for the lengths of pregnancies in the sample? Between and Enter your answers as numbers. Your answers should be accurate to 1 decimal places.

Suppose you are told that you scored  two standard deviations below the mean on a measure where the mean was 90 and the standard deviation was8. What is your score?

Mario's weekly poker winnings have a mean of $353 and a standard deviation of $67. Last week he won $185. How many standard deviations from the mean is that?

In a study 10 people were given a test. The mean test score was 78.9 points. The standard deviationfor the test scores was 5.2 points. If an 11th person takes the test and scores 77 points, predict what willhappen to the mean and standard deviation. Circle the appropriate conclusion in the sentences below. The mean will increase // decrease // stay the same.  The standard deviation will increase // decrease // stay the same.

In a psychology class, 40 students have a mean score of 89.5 on a test. Then 24 more students take the test and their mean score is 78.3.What is the mean score of all of these students together? Round to one decimal place.

You want to know the percentage of utility companies that earned revenue less than 67 million dollars. If the mean revenue was 50 million dollars and the data has a standard deviation of 7 million, find the percentage. Assume that the distribution is normal. Round your answer to the nearest hundredth.

Given a scenario where n=100 and p=0.8, find the mean.