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Quadratic
Quadratic mean =
Find the R.M.S. of these voltages measured from household current: 0, 100, 162, 162, 100, 0, −100, −162, −162, −100, 0. How does the result compare to the mean?
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Elementary Statistics
- Marginal Tax Rate The following table shows tax due for the given taxable income level for a single taxpayer. Taxable income Tax due 97, 000 21, 913 97, 050 21, 927 97, 100 21, 941 97, 150 21, 955 97, 200 21, 969 a. Show that the data in the table are linear. b. How much additional tax is due on each dollar over 97.000? c. What would you expect to be your tax due if you had a taxable income of 97, 000? of 98, 000? d. Find a linear formula that gives your tax due if your income is A dollars over 97, 000.arrow_forwardDVD Player Sales The table shows the number of DVD players sold in a small electronics store in the years 2003-2013. Year DVD players sold 2003 495 2004 513 2005 410 2006 402 2007 520 2008 580 2009 631 2010 719 2011 624 2012 582 2013 635 aWhat was the average rate of change of sales between 2003 and 2013? bWhat was the average rate of change of sales between 2003 and 2004? cWhat was the average rate of change of sales between 2004 and 2005? dBetween which two successive years did DVD player sales increase most quickly? Decrease most quickly?arrow_forwardGrade Point Average In many universities students are given grade points for each credit unit according to the following scale: A 4 points B 3 points C 2 points D 1 point F 0 point For example, a grade of A in a 3-unit course earns 43=12 grade points and a grade of B in a 5-unit course earns 35=15 grade points. A students grade point average GPA for these two courses is the total number of grade points earned divided by the number of units; in this case the GPA is (12+15)8=3.375. a Find a formula for the GPA of a student who earns a grade of A in a units of course work, B in b units, C in c units, D in d units and F in f units. b Find the GPA of a student who has earned a grade of A in two 3-unit courses, B in one 4-unit courses and C in three 3-unit courses.arrow_forward
- Using the model in Example 6, estimate the number of cases of flu on day 15.arrow_forwardThe student will design and carry out a survey.The student will analyze and graphically display the results of the survey.Instructions: As you complete each task below, check it off. Answer all questions in your summary.____Decide what data you are going to study. EXAMPLES: Here are two examples, but you may NOT use them: number of M&M’s per small bag, number of pencils students have in their backpacks.____Are your data discrete or continuous? How do you know?____Decide how you are going to collect the data (for instance, buy 30 bags of M&M’s; collect data from the World Wide Web).____Describe your sampling technique in detail. Use cluster, stratified, systematic, or simple random (using a random number generator) sampling. Do not use convenience sampling. What method did you use? Why did you pick that method?____Conduct your survey. Your data size must be at least 30.____ Summarize your data in a chart with columns showing data value, frequency, relative frequency and…arrow_forwardHere is a set of data. 188 360 460 497 559 607 620 648 683 791 816 842 969 975 Identify the 5 number summary (min, Q1, median, Q3, max) _________,_________ ,________ ,_________ ,__________arrow_forward
- A realtor studies the relationship between the size of a house (in square feet) and the property taxes (in $) owed by the owner. The table below shows a portion of the data for 20 homes in a suburb 60 miles outside of New York City. [You may find it useful to reference the t table.] Property Taxes Size 21,872 2,464 17,498 2,451 ⋮ ⋮ 29,294 2,895 Click here for the Excel Data File a-1. Calculate the sample correlation coefficient rxy. (Round intermediate calculations to at least 4 decimal places and final answers to 4 decimal places.) a-2. Interpret rxy. multiple choice 1 The correlation coefficient indicates a positive linear relationship. The correlation coefficient indicates a negative linear relationship. The correlation coefficient indicates no linear relationship. b. Specify the competing hypotheses in order to determine whether the population correlation coefficient between the size of a…arrow_forwardFill in the blanks. a. Data from one variable of a population are called _____ data.b. Data from two variables of a population are called _____ data.arrow_forwardThe data represents the heights of eruptions by a geyser. Use the heights to construct a stemplot. Identify the two values that are closest to the middle when the data are sorted in order from lowest to highest. Height of eruption (in.) 6161 3232 5050 9090 8080 5050 4040 7070 5050 6161 7373 5656 5959 6767 6060 6060 7878 7070 4848 8484 Which plot represents a stemplot of the data?arrow_forward
- Data in the table comes from the NASA Global Climate Change website. It gives the average globaltemperature, in Celsius, for the given year. Use both rows for your calculations. For this problem, youwill see how well year correlates with the average temperature. Let ? be the number of years since1984 and ? be the average global temperature in degrees Celsius.Year 1984 1986 1988 1990 1992 1994 1996 1998 2000Temp 0.16 0.18 0.38 0.45 0.22 0.31 0.33 0.61 0.40Year 2002 2004 2006 2008 2010 2012 2014 2016 2018Temp 0.63 0.54 0.64 0.54 0.72 0.64 0.75 1.02 0.85a. Make a scatterplot of the data. Being sure to clearly label each axis. Keep in mind howeach variable is defined. Based on this scatterplot, is a linear model reasonable for this data set?Briefly explain.b. Determine the correlation coefficient for this data. Interpret this value in context.c. Determine the coefficient of determination for this data. Interpret this value incontext.d.State the regression line for the data.e. What does the…arrow_forwardRunning Shoes. A shoe designer tests a new material for the soles of their most popular line of running shoes. She has 6 athletes run 100 miles with one of last years shoes and one of these new shoes, randomly assigning the new shoe to the left or right foot. Afterward, she measures the amount of wear on each of the shoes in millimeters. Test the claim that the amount of wear with the new material is different from the amount of wear with the old material. Runner 4 1 2 3 1.14 1.04 1.08 1.09 New Material Wear Old Material Wear 1.03 0.87 0.96 1.01 (b) Write the hypotheses in symbols. Ho: Hdiff-new-old = 0 Ha: Hdiff-new-old > 0 O Ho: Pdiff-new-old (a) Why are these paired data? O The top and bottom values in each column are from the same runner. Runners typically run in groups of two. There are an equal number of shoes of each type. This table does not have paired data; there is no clear relationship between the top and bottom values in any column. Each runner has a pair of shoes. -0 Ha:…arrow_forwardSolve using R calculator. Show all work.arrow_forward
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