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MATH SOLVE
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A statistician uses Chebyshev's Theorem to estimate that at least 15 % of a population lies between the values 9 and 20. Use this information to find the values of the population mean, μ , and the population standard deviation σ.
General
2 months ago
A survey of 400 college seniors resulted in the following crosstabulation regarding their undergraduate major and whether or not they plan to go to graduate school. What percentage of the undergraduates surveyed are majoring in Engineering?
General
2 months ago
Let X, Y , Z be three random variables which satisfy the following conditions: Var(X) = 4, Var(Y ) = 9, Var(Z) = 16. Cov(X, Y ) = −2, Cov(Z, X) = 3, and Y and Z are independent. Find: (a) Cov(X + 2Y, Y − Z). (b) Var(3X − Y ). (c) Var(X + Y + Z)
General
2 months ago
The force F (in newtons) of the hydraulic cylinder in a press is proportional to the square of sec x where x is the distance (in meters) that the cylinder is extended in its cycle. The domain of F is [0, pi/3], and F(0) = 500.A) find F as a function of x.F(x)=___________B) find the average force exerted by the press over the interval [0, pi/3] (round your answer to 1 decimal place)F= _________? N
General
2 months ago
The designer also programs a bird with a path that can be modeled by a quadratic function. The bird starts at the vertex of the path at (0, 20) and passes through the point (10, 8). What is the slope of the line that represents the turtle's path?
General
2 months ago
A soccer ball manufacturer wants to estimate the mean circumference of soccer balls within 0.05 in. (a) Determine the minimum sample size required to construct a 99% confidence interval for the population mean. Assume the population standard deviation is 0.20 in. (b) Repeat part (a) using a standard deviation of 0.40 in. Which standard deviation requires a larger sample size? Explain. (a) The minimum sample size required to construct a 99% confidence interval using a population standard deviation of 0.20 in. is balls. (Round up to the nearest integer.) (b) The minimum sample size required to construct a 99% confidence interval using a standard deviation of 0.40 in. is balls. (Round up to the nearest integer.) A population standard deviation of in. requires a larger sample size. Due to the increased variability in the population, a sample size is needed to ensure the desired accuracy.
General
2 months ago
Two accounting professors decided to compare the variance of their grading procedures. To accomplish this, they each graded the same 10 exams, with the following results: Mean Grade Standard Deviation Professor 1 79.3 22.4 Professor 2 82.1 12.0 At the 10% level of significance, what is the decision regarding the null hypothesis? A) Reject the null hypothesis and conclude the variances are different. B) Fail to reject the null hypothesis and conclude no significant difference in the variances. C) Reject the null hypothesis and conclude the variances are the same. D) Fail to reject the null hypothesis and conclude the variances are the same.
General
2 months ago
Consider the sequence −8, −4, 0, 4, 8, 12, ellipsis. Select True or False for each statement. A recursive rule for the sequence is f(1) = −8; f(n) = −4 (n − 1) for all n ≥ 2. A True B False An explicit rule for the sequence is f(n) = −8 + 4 (n − 1). A True B False The tenth term is 28.
General
2 months ago
How many different license plates are possible if each contains 3 letters (out of the alphabet's 26 letters) followed by 2 digits (from 0 to 9)? How many of these license plates contain no repeated letters and no repeated digits?
General
2 months ago
A bank wishes to estimate the mean credit card balance owed by its customers. The population standard deviation is estimated to be $300. If a 98 percent confidence interval is used and an interval of $78 is desired, how many customers should be sampled?A. 725B. 80C. 57D. 320
General
2 months ago
a worker is tiling the floor of a rectangular room that is 12 feet by 15 feet. THe tiles are square with side lengths 1 1/3 feet. How many tiles are needed to cover the entire floor?
General
2 months ago
Ella's college professors assign homework independently from each other. ella knows that there is a 60% chance that she will have math homework tonight and a 70% chance that she will have english homework. what is the probability that she will not have math or english homework tonight? 10% 12% 42% 70%
General
2 months ago
In applied life data analysis (wiley, 1982), wayne nelson presents the breakdown time of an insulating fluid between electrodes at 34 kv. the times, in minutes, are as follows: 0.05, 0.93, 0.92, 1.18, 2.87, 3.30, 4.30, 4.68, 4.78, 6.46, 7.29, 7.88, 8.36, 12.16, 31.66, 32.59, 33.88, 36.80, and 72.89. calculate the sample mean and sample standard deviation. round the answers to 3 decimal places.
General
2 months ago
which is most likely the equation of the line shown on the graph?
General
2 months ago
1. What is the wave speed of a wave that has a frequency of 100 Hz and a wavelength of 0.30 m?2. What is the wave speed of a wave that has a frequency of 50 Hz and a wavelength of 0.10 m?3. What is the frequency of a wave that has a wave speed of 20 m/s and a wavelength of 0.50 m?4. What is the frequency of a wave that has a wave speed of 80 m/s and a wavelength of 0.20 m?5. What is the frequency of a wave that has a wave speed of 120 m/s and a wavelength of 0.40 m?6. What is the wavelength of a sound wave that has a speed of 340 m/s and a frequency of 440 Hz?7. What is the wavelength of a sound wave that has a speed of 340 m/s and a frequency of 880 Hz?8. What is the wavelength of a sound wave that has a speed of 250 m/s and a frequency of 400 Hz?9. What is the wave speed of a wave that has a frequency of 50 Hz and a wavelength of 2.0 m?10. What is the wave speed of a wave that has a frequency of 100 Hz and a wavelength of 0.50 m?please answer fast
General
2 months ago
A cable hangs between two poles of equal height and 30 feet apart. set up a coordinate system where the poles are placed at x=−15 and x=15, where x is measured in feet. the height (in feet) of the cable at position x i
General
2 months ago
Two isosceles triangles have the same base length. the legs of one of the triangles are twice as long as the legs of the other. find the lengths of the sides of the triangles of their perimeters are 23 cm and 43 cm.
General
2 months ago
a survey asked 50 students if they play an instrument and if they are in band. 25 students play an instrument 20 are in a band and 30 are not in a band. which table shows these data correctly entered in a two way frequency table?
General
2 months ago
A triangular flowerbed is being planted inside a circular area of grass. What is the area of the entire circular region (including the flowerbed)? (Use 3.14 for π .) 10,562.96 ft 2 182.12 ft 2 2,640.74 ft 2 91.06 ft 2
General
2 months ago
Ron is taking an inventory at his store. Based on previous sales, he predicted sales of 25 folders and 230 erasers. He actually sold 30 folders and 200 erasers. What is the percent error for the erasers?
General
2 months ago
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