How much does a sleeping bag cost? Let's say you want a sleeping bag that should keep you warm in temperatures from 20°F to 45°F. A random sample of prices ($) for sleeping bags in this temperature range is given below. Assume that the population of x values has an approximately normal distribution. 115 110 40 45 65 60 30 23 100 110 105 95 105 60 110 120 95 90 60 70   (a) Use a calculator with mean and sample standard deviation keys to find the sample mean price x and sample standard deviation s. (Round your answers to four decimal places.) x=$ s=$

Select all true statements below (Multiple or none can be true). With a large, representative sample, the histogram of the sample data will follow the normal curve closely. If two lists of numbers have exactly the same average of 50 and SD of 10, then the percentage of entries between 40 and 60 must be exactly the same for both lists. Half of a list of numbers is always below its average. The median and average of a list of numbers are not necessarily close together.

Use the Empirical Rule. The mean speed of a sample of vehicles along a stretch of highway is 71 miles per​ hour, with a standard deviation of 5 miles per hour. Estimate the percent of vehicles whose speeds are between 61 miles per hour and 81 miles per hour.​ (Assume the data set has a​ bell-shaped distribution.)   Approximately ________ ​% of vehicles travel between 61 miles per hour and 81 miles per hour.

Find the mean and standard deviation for the individualized instruction scores. Scores Individualized Instruction 50 - 59 4 60 – 69 8 70 - 79 6 80 - 89 8 90 - 99 3 Mean = (Round to the nearest hundredth.)

Find the mean of the data summarized in the given frequency distribution. Compare the computed mean to the actual mean of 51.9 miles per hour. Speed (miles per hour) Frequency 42 - 45 46-49 50 - 53 54 -57 58 -61 25 15 The mean of the frequency distribution is miles per hour. (Round to the nearest tenth as needed.)

The Focus Problem at the beginning of this chapter asks you to use a sign test with a 10% level of significance to test the claim that the overall temperature distribution of Madison, Wisconsin, is different (either way) from that of Juneau, Alaska. The monthly average data (in °F) are as follows. Month Jan. Feb. March April May June Madison 17.8 21.4 31.8 46.9 57.1 67.8 Juneau 22.8 27.5 31.8 38.6 46.2 52.7 Month July Aug. Sept. Oct. Nov. Dec. Madison 71.9 69.5 60.8 51.7 35.6 22.2 Juneau 55.6 54.9 49.3 41.1 32.5 26.3 (a) What is the level of significance? (b) Compute the sample test statistic. (Use 2 decimal places.) (c) Find the P-value of the sample test statistic

Using your calculator, find the range and standard deviation, round to two decimals places:The table below gives the number of hours spent watching TV last week by a sample of 24 children. 90 50 46 31 52 83 51 90 72 47 25 57 53 62 65 89 35 49 32 21 77 30 91 13 Range = Standard Deviation =