An estimation of a population parameter believed to contain

An estimation of a population parameter believed to contain the value of believed to contain the value of the parameter is known as From a population with a standard deviation of 20, a sample of 100 Items is selected. At 95% confidence, the margin of error is In order to determine an interval for the mean of .1 population with unknown standard deviation a sample of 87 Items is selected. The mean of the sample is determined to be 30. The number of degrees of freedom for reading the t value Is In order to estimate the average time spent on the computer terminals per student at a local university, data were collected from a sample of 81 students over a one week period. Assume the population standard deviation is 1.2 hours. The standard error of the mean is

Solution

10) a. Confidecne onterval gives an interval in which the parameter value is expected to lie.

11) c. Formula is 1.96*s/sqrt(n)=1.96*20/10

12) c. degrees of freedom is n-1.

13) d. formula is s/sqrt(n).