A random sample of 10 houses heated with natural gas in a particular area is selected, and the amount of gas (in therms) used during the month of January is determined for each house. The resulting observations are as follows:
114 121 103 129 140 106 161 92 126 151
(a) Let μJ denote the average gas usage during January by all houses in this area. Compute a point estimate of μJ in therms.
(b) Suppose that 10,000 houses in this area use natural gas for heating. Let Ï„ denote the total amount of gas used by all of these houses during January. Estimate Ï„ using the given data in therms. What statistic did you use in computing your estimate? Sample variance, sample range, sample mean, or sample standard deviation?
(c) Use the given data to estimate p, the proportion of all houses that used at least 100 therms.
(d) Give a point estimate of the population median usage based on the given sample in therms. Which statistic did you use? Population variance, population mean, sample median, or sample standard deviation?
