Probabilities related to a sample mean.

The breaking strength of a rivet has a mean value of 10,000 psi and a standard deviation of 500 psi. a. What is the probability that the sample mean breaking strength for a random sample of 40 rivets is between 9900 and 10,200. b. If the sample size had been 15 rather than 40, could the probability requested in part (a) be calculated from the given information?

Joint probability distribution and random samples

54. Suppose the sediment density (g/cm) of a randomly selected specimen from a certain region is normally distributed with mean ... a. If a random sample of 25 spediemns is selected, what is the probability ... b. How large a sample size would be required to ensure the the first probability in part (a) ... Please see attachment for complete question. Thanks.

Point Estimation in Statistics

20. A random sample of n bike helmets manufacturesd by a certain company is selected. Let X = ... a. Derive the maximum likelihood esitmator ... b. Is the esitmator of part (a) unbiased? c. If n = 20 and x = 3, what is the mle of the probability ...

Point Estimation in Statistics

22. Let X denote the proportion of alloted time that a randomly selected student spends working on a certain aptitude test. Suppose the pdf of X is ... a. Use method of moments to obtain an estimator ... b. Obtain the maximum likelihood esitmator ... Please see attachment for complete question. Thank you!

Jointly Distributed Random Variables

10. ... Suppose that X and Y are independent with each uniformly distributed on the interval ... a. What is the joint pdf? b. What is the probability that they both arrive between ... c. If the first one to arrive will wait only 10 minutes before leaving to eat elsewhere, what is the probability ... (Please see attachment for complete question. Thank you).