A researcher calculated a confidence interval for the mean amount of time it took a car to stop from 60 miles per hour. His results were (6.9 seconds, 7.8 seconds) with 99% confidence. Determine the proper notation and the value of both the point estimate and margin of error for the mean stopping time. WE USE GREEK LETTERS FOR PARAMETERS (population), ROMAN LETTERS FOR STATISTICS (sample)

Diana takes a state driver’s license test and receives a score of 70. The mean score on this state exam is 76 with a standard deviation of 5. Calculate Diana’s z-score and determine if her score would be considered unusual.   Hints: z =

A father records the amount of milk remaining in all 1 gallon cartons on their shopping day. Which of the following vocabulary words would be correct to describe the variable “The amount of milk remaining in a 1 gallon carton”? Hint: is the variable countable? measurable ?

Would it be unusual for 16 of the bulbs to be defective? Justify your answer. .

Resting heart rates for a population are normally distributed with a mean of 72 bpm and a standard deviation of 10 bpm. If a sample of 16 people is randomly chosen, find the probability their mean heart rate is more than 75 bpm. Hints: *normalcdf

Weights of newborn babies are normally distributed with a mean of 7.5 lb and a standard deviation of 1.25 lb. A newborn whose weight is in the lowest 4% of the population is classified as low birth weight. Find the cutoff for the lowest 4% of birth weights.  

Richard’s total cholesterol level is measured to be 135 milligrams per deciliter (mg/dl). This level corresponds to a z-score of —1.94. Choose the correct interpretation of this z-score. Hint: Z score is a measure of position. It represents the number of standard deviations from the mean 

Use the following information for problems #11 and #12. A manufacturer of halogen bulbs knows that 3% of the production of their bulbs will be defective.  Suppose that a consumer purchases a package of 300 bulbs. Compute the mean and standard deviation of the population.   Hints WE USE GREEK LETTERS FOR PARAMETERS (population), ROMAN LETTERS FOR STATISTICS (sample)

The Collin College library has a display case that can hold 4 books at a time. If they have received 10 new books, how many different random samples of 4 books can be chosen?  

Below are the histogram and boxplot of the temperatures. Identify the correct notation for the mean and median, then use the graphs, along with the measures of center, to determine which would be the best measure of center for the temperature data set. Hints: Mean = Median (Normally distributed) Mean