Assuming that the tire mileage is normally distributed and the mean number of miles to failure is not known and a known ? = 3,700 miles. using your sample of 41 tires as your estimate of the mean (x bar); what is the upper and lower bound of a 95% confidence interval? (this was your question #2): suppose when you did this this calculation you found the error to be too large and would like to limit the error to 1000 miles. what should my sample size be?

Apsychology student wishes to investigate differences in political opinions between business majors and political science majors at her college. she randomly selects 100 students from the 260 business majors and 100 students from the 180 political science majors. does this sampling plan result in a simple random sample? why or why not? no, because each group of 200 students in the sample does not have the same chance of being selected. yes, because each group of 200 students in the sample has the same chance of being selected. no, because each individual student does not have an equal chance of being selected. yes, because each individual student has the same chance of being selected.

Aschool had an election where the candidates received votes in the ratio 1: 2: 3. if the winning candidate received 210 votes, how many total people voted in the election?

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?