Suppose you work at a large tire distribution center. The tires’ average tread life has been 50,000 miles with a standard deviation of 5,000 miles. At the end of the year, the company can reevaluate their supply contract. There are four supply options for the next contract: the current supplier or one of three competitors.

The current supplier produces tires with an average tread life of 50,000 miles with a standard deviation of 5,000 miles. Competitor A claims to produce tires with an average tread life of 52,000 miles with a population standard deviation of 8,000 miles. Competitor B claims to produce tires with an average tread life of 50,000 miles with a population standard deviation of 3,000 miles. Competitor C claims to produce tires with an average tread life of 60,000 miles with a population standard deviation of 12,000 miles.

Based on your evaluations of the three competitors, you must recommend a supply option for the next contract. Recall, you are allowed to choose the current supplier.

Based on tests of a certain automobile, engineers have found that the miles per gallon in highway driving are normally distributed, with a mean of 31 miles per gallon and a standard deviation of 3.4 miles per gallon. 12 of these automobiles are randomly selected and the miles per gallon for each car are recorded.

What is the probability that the mean miles per gallon of this sample exceeds 33 miles per gallon?

Would this be considered unusual?

A trucking company determined that the distance traveled per truck per year is normally​ distributed, with a mean of 60 thousand miles and a standard deviation of 10 thousand miles. Complete parts​ (a) through​ (d) below.

a. What proportion of trucks can be expected to travel between 48 and 60 thousand miles in a​ year?

b. What percentage of trucks can be expected to travel either less than 40 or more than 75 thousand miles in a​ year?

c. How many miles will be traveled by at least 85​% of the​ trucks?

d. What are your answers to parts​ (a) through​ (c) if the standard deviation is 8 thousand​ miles? I

f the standard deviation is 8 thousand​ miles, the proportion of trucks that can be expected to travel between 48 and 60 thousand miles in a year is . ​(Round to four decimal places as​ needed.)

If the standard deviation is 8 thousand​ miles, the percentage of trucks that can be expected to travel either less than 40 or more than 75 thousand miles in a year is . ​(Round to two decimal places as​ needed.)

If the standard deviation is 8 thousand​ miles, the number of miles that will be traveled by at least 85​% of the trucks is . ​(Round to the nearest mile as​ needed.)

According to the Environmental Protection Agency (EPA), the 2018 Toyota Camry L drives an average of 420.5 miles on a full tank of gas. Assume the mileage follows a normal distribution with a standard deviation of 50 miles. Answer the following questions:

17.) Determine the number of miles that the car will travel with 90%, 30%, and 50% probability on a full tank of gas.

18.) Determine the UPPER AND LOWER value(s) for the interval of miles traveled on a full tank of gas around the mean that includes approximately 68% of miles for this car.

19.) Determine the UPPER AND LOWER value(s) for the interval of miles traveled on a full tank of gas around the mean that includes approximately 95% of miles for this car.

20.) Determine the UPPER AND LOWER value(s) for the interval of miles traveled on a full tank of gas around the mean that includes approximately 99.7% of miles for this car.

Descriptive statistics: What do all of those numbers mean in terms of the problem. Organizing and summarizing data is called descriptive statistics. Two ways to summarize data are by graphing and by using numbers (for example, finding an average). A statistical graph is a tool that helps you learn about the shape or distribution of a sample or a population. Our data is examining the distance (miles) between twenty retail stores, and a large distribution center The Mean: (84.05 miles) shows the arithmetic mean of the sample data. Standard E: (7.71822 miles) shows the standard error of the data set, which is the difference between the predicted value and the actual value. Median: (86.5 miles) shows the middle value in the data set, which is the value that separates the largest half of the values from the smallest half of the values Mode: (96 miles) shows the most common value in the data set. Standard [: (34.51693 miles) shows the sample standard deviation measure for the data set. Sample Va: (1191.418 miles) shows the sample variance for the data set, the squared standard deviation. Kurtosis: (-0.48156 miles) shows the kurtosis of the distribution. Skewness: (0.210738 miles) shows the skewness of the data set’s distribution. Range: (121 miles) shows the difference between the largest and smallest values in the data set. Minimum: ( 29 miles) shows the smallest value in the data set. Maximum: (150 miles) shows the largest value in the data set. Sum (1681 miles) adds all the values in the data set together to calculate the sum. Count (20 miles) counts the number of values in a data set.

Use the Empirical Rule. The mean speed of a sample of vehicles along a stretch of highway is 71 miles per​ hour, with a standard deviation of 4 miles per hour. Estimate the percent of vehicles whose speeds are between 63 miles per hour and 79 miles per hour.​ (Assume the data set has a​ bell-shaped distribution.) Approximately what ​% of vehicles travel between 63 miles per hour and 79 miles per hour.

The distance a student lives (in miles) from their classroom is approximately normally distributed with a mean of 5 miles and a standard deviation of 1.5 miles. Use the normal table to find the probabilities.

a) How far away do the closest 15% of students live?

b) What is the probability that a student will live less than 7 miles away?

c) What is the probability that a student will live further away than 3 miles

or less than 7 miles away?

The distance a student lives (in miles) from their classroom is approximately normally distributed with a mean of 5 miles and a standard deviation of 1.5 miles. Use the normal table to find the probabilities.

a) How far away do the closest 15% of students live?

b) What is the probability that a student will live less than 7 miles away?

c) What is the probability that a student will live further away than 3 miles

or less than 7 miles away?

Use the table below to solve this problem.

Suppose the wealth effect is such that a $10 change in wealth produces a $1 change in consumption at each level of income. Assume real estate prices tumble such that wealth declines by $160.

Instructions: Enter your answers as whole numbers.

a.What will be the new level of consumption at the $680 billion level of disposable income?

b. What will be the new level of saving?

Prior to adjustment at the end of the year, the balance in Trucks is $302,210 and the balance in Accumulated Depreciation—Trucks is $100,920. Details of the subsidiary ledger are as follows: Estimated Accumulated Depreciation at Miles Operated Truck No. Cost Residual Value Useful Life Beginning of Year During Year 1 $83,960 $15,360 245,000 miles — 20,600 miles 2 51,050 5,930 300,800 miles $14,700 33,800 miles 3 77,486 12,910 201,800 miles 62,180 8,100 miles 4 89,714 22,010 241,800 miles 24,040 22,500 miles A. Determine for each truck the depreciation rate per mile and the amount to be credited to the accumulated depreciation section of each subsidiary account for the miles operated during the current year. Keep in mind that the depreciation taken cannot reduce the book value of the truck below its residual value. Round rate per mile answers to the nearest cent. B. Journalize the entry on December 31 to record depreciation for the year. Refer to the Chart of Accounts for exact wording of account titles.