# Question: A medical research worker intends to use the mean of

A medical research worker intends to use the mean of a random sample of size n = 120 to estimate the mean blood pressure of women in their fifties. If, based on experience, he knows that σ = 10.5 mm of mercury, what can he assert with probability 0.99 about the maxi-mum error?

## Relevant Questions

With reference to Exercise 11.22, suppose that the research worker takes his sample and gets = 141.8 mm of mercury. Construct a 98% confidence interval for the mean blood pressure of women in their fifties. In a study of television viewing habits, it is desired to estimate the average number of hours that teenagers spend watching per week. If it is reasonable to assume that σ = 3.2 hours, how large a sample is needed so that ...The following are the heat- producing capacities of coal from two mines (in millions of calories per ton): Assuming that the data constitute independent random samples from normal populations with equal variances, construct ...Use the result of Exercise 11.13 to rework Exercise 11.45, given that the poll has reason to believe that the true proportion does not exceed 0.30. With reference to Exercise 11.34, construct a 98% confidence interval for the ratio of the variances of the two populations sampled. In exercise A study of two kinds of photocopying equipment shows that 61 failures of the ...Post your question