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Quadratic
Find the R.M.S. of these voltages measured from household current: 0, 60,110, −110, −60.0. How does the result compare to the mean?
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EBK ELEMENTARY STATISTICS
- Perimeter of a square Write a formula for the perimeter P of a square of its area A.arrow_forwardAerobic Power Aerobic power can be thought of as the maximum oxygen consumption attainable per kilogram of body mass. There are a number of ways in which physical educators estimate this. One method uses the Queens College Step Test. In this test, males step up and down a 16-inch bleacher step 24 times per minute for 3 minutes, and females do 22 steps per minute for 3 minutes. Five seconds after the exercise is complete, a 15-second pulse count P is taken. Maximum oxygen consumption M, in milliliters per kilogram, for males is approximated by M=111.3-1.68P. For females, the recommended formula is F=65.81-0.74P. a. Calculate the maximum oxygen consumption for both a male and a female who show a 15-second pulse count of 40. b. What 15-second pulse count for a male will indicate a maximum oxygen consumption of 35.7 milliliters per kilogram? c. What 15-second pulse count will indicate the same maximum oxygen consumption for a male as for a female? d. What maximum oxygen consumption is associated with your answer in part c?arrow_forwardKeplers Third Law According to Keplers third law of planetary motion, the mean distance D, in millions of miles, from a planet in our solar system to the sun is related to the time P, in years, that it takes for the planet to complete a revolution around the sun, and the relationship is D=93P2/3. It takes the planet Pluto 249 years to complete a revolution around the sun. What is the mean distance from Pluto to the sun? What is the mean distance from Earth to the sun? Give your answers to the nearest million miles.arrow_forward
- Stock Turnover at Retail In retail sales, an important marker of retail activity is the stock turnover at retail. This figure is calculated for a specific period of time as the total net sales divided by the retail value of the average stock during that time, where both are measured in dollars. As a formula, this is written Stockturnover=NetsalesAveragestockatretail. This formula expresses stock turnover as a function of net sales and average stock at retail. a. Suppose that your store had net sales of 682, 000 in mens shoes over the past six months and that the retail value of the average stock of mens shoes was 163, 000. What was the stock turnover at retail for that time period? b. Suppose that in a certain month, your stores net sales of womens dresses were 83, 000 and that the usual stock turnover at retail is 0.8 per month. What do you estimate to be your stores average stock at retail? c. Solve the equation for average stock at retail- that is, write a formula giving average stock at retail as a function of stock turnover and net sales. d. Suppose that in a certain time period, your store had an average stock of socks with a retail value of 45, 000 and a stock turnover at retail of 1.6. What were the stores net sales of socks during that time period? e. Solve the equation for net sales- that is, write a formula giving net sales as a function of stock turnover and average stock at retail.arrow_forwardRunning Speed A man is running around a circular track that is 200 m in circumference. An observer uses a stopwatch to record the runner’s time at the each of each lap, obtaining the data in the following table. (a) What was the man’s average speed (rate) between 68 s and 152 s? (b) What was the man’s average speed between 263 s and 412 s? (c) Calculate the man’s speed for cadi lap, Is he slowing down, speeding up, or neither?arrow_forwardSpache Readability Formula The Spache Readability Formula3 is designed to categorize reading materials for grades 1 through 3. For a passage of text, the variables are S, the number of sentences: W, the number of words; and U, the number of unfamiliar words words not on a specific list. The formula as revised for the grade level is Grade level =0.121WS+0.082U+0.659. The calculated grade level is rounded down to its whole number part. For example, 2.6 is round down to 2. In this exercise, we consider passages having 200 words and using 10 unfamiliar words. a. As the number of sentences increases, does grade level increase or decrease? b. What is the maximum possible number of sentence? Can there be more sentences than words? c. What is the minimum number of sentences that would put this passage at the second-grade level?arrow_forward
- Running Speed A man is running around a circular track that is 200 m in circumference. An observer uses a stopwatch to record the runners time at the end of each lap, obtaining the data in the following table. aWhat was the mans average speed rate between 68 s and 152 s? bWhat was the mans average speed between 263 s and 412 s? cCalculate the mans speed for each lap. Is he slowing down, speeding up or neither? Time s Distance m 32 200 68 400 108 600 152 800 203 1000 263 1200 335 1400 412 1600arrow_forwardSpeed of Sound in the North Atlantic The speed of sound in ocean water is 1148.94meterspersecond, provided that the ocean water has a salinity of 35 35partsperthousand, the temperature it 0degreesCelsius, and the measurement is taken at the surface. If any one of these three factors varies, the speed of sound also changes. Different oceans often differ in salinity. In the North Atlantic Central Water the main body of water for the northern half of the Atlantic Ocean, the salinity can be determined from the temperature, so the speed of sound depends only on temperature and depth. A simplified polynomial formula for velocity in this body of water is V=1447.733+4.7713T0.05435T2+0.0002374T3+0.0163D+1.675107D27.1391013TD3 Here V is the speed of sound in meters per second, T is the water temperature in degrees Celsius, and D is depth in meters. This formula is valid for depths up to 8000 meters and for temperatures between 0 and 30 degrees Celsius. a. What type of polynomial is V as a function of T alone? Of D alone? b. For a fixed depth of 1000meters, write the formula for V in terms of T alone. c. Graph V as a function of T for the fixed depth of 1000meters. d. What is the concavity of the graph from part c? What does this imply about the speed of sound at that depth as temperature increases?arrow_forwardBacteria Culture A certain type of bacteria divides every 5s. If three of these bacteria are put into a petri dish, how many bacteria are in the dish at the end of 1min?arrow_forward
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