Standard Error Of Mean?

posted by .

In a random sample of 30 tires of the same type, it is found that the average life span of a tire is 36,200 miles with a standard deviation of 3,800 miles. Find the standard error of the mean.

a 126.67
b 693.78
c 9.53
d 587.24

  • Standard Error Of Mean? -

    SEm = SD/√n

    √30 = 5.48

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Statistics

    data from sample of 400 cases, variable has 95% confidence interval of 54.3 to 54.7 I found the mean- how do i find standard error- step by step please. Standard error = sd/√n Note: sd = standard deviation; n = sample size. You'll …
  2. Math

    In a random sample of 30 tires of the same type, it is found that the average life span is 36,200 miles with a standard deviation of 3800 miles. Find the interval about the sample mean such that the probability is 0.77 that the mean …
  3. Statistics

    A purchasing agent for a trucking company is shopping for replacement tires for their trucks from two suppliers. The suppliers' prices are the same. However, Supplier A's tires have an average life of 60,000 miles with a standard deviation …
  4. Statistics

    A purchasing agent for a trucking company is shopping for replacement tires for their trucks from two suppliers. The suppliers' prices are the same. However, Supplier A's tires have an average life of 60,000 miles with a standard deviation …
  5. math

    a tire manufacturer believes that the tread life of its tires are normally distributed and will lst an average of 60,000 miles with a standard deviation of 3,000 miles. sixty-four randomly selected tires were tested and the average …
  6. statistics

    According to internal testing done by the Get-A-Grip tire company, the mean lifetime of tires sold on new cars is 23,000 miles, with a standard deviation of 2500 miles. a) If the claim by Get-A-Grip is true, what is the mean of the …
  7. statistic

    one of the major U.S. tire makers wishes to review its warranty for their rainmaker tire. The warranty is for 40,000 miles. The tire company beleives that the tire actually lasts more than 40,000 miles. A sample of 49 tires reveales …
  8. Statistics

    In an essay of 250-500 words, thoroughly address the following items and respond to the related questions: 1.Define the term standard deviation. Why is it important to know the standard deviation for a given sample?
  9. mekele university

    the lytton rubber company wishes set a minimum mileage guarantee on its new Mx 100 tire. Tests reveal the mean mileage is 67,900 with the standard deviation of 2,050 miles and that the deviation follows normal distribution. They want …
  10. Statistics

    QUESTION 1 Use the following scenario and data for all the questions The lives of Lithium batteries used in a type of cell phones are normally distributed with an unknown standard deviation. A simple random sample of equation batteries …

More Similar Questions