Estimate of the average tread life

Assignment Help Basic Statistics
Reference no: EM1319089

1. Suppose a research firm conducted a survey to determine the average amount of money steady smokers spend on cigarettes during a week. A sample of 100 steady smokers revealed that the sample mean is $20 and the sample standard deviation is $5. What is the probability that a sample of 100 steady smokers spend between $19 and $21?

2. Mileage tests were conducted on a randomly selected sample of 100 newly developed automobile tires. The average tread wear was found to be 50,000 miles with a standard deviation of 3,500 miles. What is the best estimate of the average tread life for the entire population of these tires?

Reference no: EM1319089

Questions Cloud

Use graph to solve question : Use graph to solve question
Determining sample size using cofident : How large sample size must be taken to be 95% confident.
Probability for the mean weight for a sample : What is the probability that the mean weight for a sample of 40 trout exceeds 405.5 grams?
Assume to two firms in an industry with an index : Assume to two firms in an industry with an index of 5,000 announce a merger. The U.S. Justice Department concludes the merger will boost the index to 5,500. The antitrust authorities will most likely.
Estimate of the average tread life : What is the best estimate of the average tread life for the entire population of these tires?
A goodness of fit test and test of independence : Last school year, student body of a local university consisted of 30% freshmen, 24% sophomores, 26% juniors, and 20% seniors. A sample of 300 students taken from this year's student body showed the following number of students in each classificati..
What is unusual about this market : Illustrate what is unusual about this market. Give an example of a good or service to might be characterized by this unusual market attribute.
Determining normality assumption : If statistically significant, do you believe the difference is large enough to be significant? If so, to whom, and explain why? Is normality assumption fulfilled? Describe.
Place the points in a number line : Place the points in a number line.

Reviews

Write a Review

Basic Statistics Questions & Answers

  Normal distributed with mean

In healthy adults, x is approximately normally distributed with mean µ = 38 and standard deviation σ = 12. What is the probability that:

  Body weight that is approximately normally distributed

Fawns Fawns among1 or 5 months old in Mesa Verde National Park have a body weight that is approximately normally distributed with mean

  What is the probability the son attended college

The following data from a sample of 100 families show the record of college attendance by fathers and their oldest sons: in 22 families, both father and son attended college; in 31 families, neither father nor son attended college; in 12 families,..

  Poisson distribution with mean

Suppose that the number of babies born during an hour at a hospital's maternity wing follows a Poisson distribution with a mean of 4 per hour.

  Biggest problem facing education today

Survey on What do you think is the biggest problem facing education today. One problem with exit polls may be that the wrong "key precincts" were chosen.

  Estimating probability based on the discrete distribution

The casino game craps is based on rolling two dice. Here is the assignment of probabilities to the sum of numbers on the up face when two dice are rolled:

  Romance usa presentbooks sold are of romance genre

Romance USA present reported that 11 percent of all books sold are of the romance genre. If a local bookstore sells 316 books on a given day

  Calculating waiting time and average queue length

Simulate both one-and two-teller systems, calculate waiting time, average queue length, and percentage utilization for each system.

  Determining three quartiles and box-and-whisker plot

4  7  7  5  2  9  7  6  8  5  8  4  1  5  2  8  7  6  6  9. (a) Determine three quartiles and (b) draw box-and-whisker plot of the data.

  Level of significance-variability unchanged

Assuming that the variability is unchanged (i.e.,  σ  = 6), is there sufficient evidence to suggest that the strength of the product has increased at the 1% level of significance?

  Difference in the proportions

Construct a 95% confidence interval for the difference in the proportions of women and men who have regular exercise programs.

  Computing critical value and null hypothesis

What is the null hypothesis?  Use   α =0.05. Compute critical value.  Use   α =0.05.

Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd