Let Z be a standard normal random variable. Calculate the following probabilities and round your responses to at least three decimal places. P (Z > - 0.64) = P (Z ≤(less than or equal to) - 1.39) = P (1.38 < Z < 2.07) =
1) According to an IRS study, it takes an average of 330 minutes for taxpayers to prepare, copy, and electronically file a 1040 tax form. A consumer watchdog agency selects a random sample of 40 taxpayers and finds the standard deviation of the time to prepare, copy, and electronically file form 1040 is 80 minutes. What assumpti
11. An automaker guarantees its particular type of automotive transmissions for 90,000 km. Tests have shown that such transmissions have an average life of 135,000 km with a standard deviation of 22,500 km. If the lives of these transmissions are normally distributed, what is the probability that a car will be returned to the
The mean of normal probability distribution is 60; the standard deviation is 5. a. About what percent of the observations lie between 55 and 65? b. About what percent of the observations lie between 50 and 70? c. About what percent of the observations lie between 45 and 75? See the attached file.
Please find attached problem. (a) A five-gear assembly is put together with spacers between the gears. The mean thickness of the gears is 5.030 cm with a standard deviation of 0.008cm. The mean thickness of the spacers is 0.140 cm with the standard deviation of 0.005 cm. Find the mean and standard deviation of the assembled u
How do you develop a bell curve for 1,000 cases: With a given mean of 20 and a standard deviation of 2, how do you compute the -3,-2,-1 (mean), +1,+2,+3 points along the baseline of the curve (assuming the curve is normal)? Then repeat the mean of 10 pounds and the standard deviation is 4.5. Repeat again with a mean of 4 secon
4. (1) Assume that the readings on the thermometers are normally distributed with a mean of 0o and standard deviation of 1.00o C. A thermometer is randomly selected and tested. Draw a diagram and find the probability in degrees. Between -1.18 and 2.15 (2) The lengths of pregnancies are normally distributed with a mean of 2
The mean starting salary for college graduates in the spring of 2004 was $36,280. Assume that the distribution of starting salaries follows the normal distribution with a standard deviation of $3,300. What percent of the graduates have starting salaries: a. Between $35,000 and $40,000? b. More than $45,000? c. Between $40,0
This problem requires the use "Crystal Ball", the popular commercial spreadsheet add-in. For clarity, it is distributed by Decisioneering, Inc. This problem specifically requires that Excel and "Crystal Ball" (and OptQuest as applicable) be used - and not any other software choices. The link below directs you to a free 7-day t
Let x1 and x2 be independent normal random variables, x1 n(ui,oi2), and let y1 = x1 and y2 = x1+x2
I need some help answering this question without calculus: In 1973, Charles Tart ran an experiment at UC Davis to test for ESP abilities. Tart used an electronic random number generators called the Aquarius with four "targets". The machine randomly picked one of the fours targets, and the subject guessed which target the machi
(See attached file for full problem description with equations) (Steiner's theorem) If IA is the moment of inertia of a mass distribution of total mass M with respect to an axis A through the center of gravity, show that its moment of inertia IB with respect to an axis B, which is parallel to A and has the distance k from it,
The service life of a certain product is normally distributed. Suppose 94 percent of the items have lives exceeding 2000 h and 3.51 percent have lives exceeding 16,240 h. Find the mean and standard deviation of the service life.
The resistances of carbon resistors of 1500 ohm nominal value are normally distributed with µ = 1500 and standard deviation = 200. a. What proportion of resistors is expected to have resistance greater than 1150 ohm? b. Within plus and minus what amount around the mean do 80 percent of resistances fall?
How do you verify that the assumption of a normal distribution is correct if you have only the mean and standard deviation? What could you do if you actually have the data? In my case, the sample size is 1000, mean 40, and SD 10.
How do you verify that the assumption of a normal distribution is correct if you have only the mean and standard deviation? What could you do if you actually have the data? In my case, the sample size is 1000; mean 40, and SD 10. If you then took a sample of 20 from the original sample of 1000, is the expected value 40? How
I have a random sample of n = 16 scores with a normal distribution, mean of 50 and standard deviation of 10. I need to calculate what range of values has a 95% probability of containing the sample mean. Here is where I get stuck. I have been provided the answer and it is 45.13 to 54.87 (50 +/- 4.87). I don't know how to
(See attached file for full problem description) --- 1. The Trail Making Test (TMT) is frequently used in neuropsychological assessment to provide a quick estimate of brain damage in humans. To investigate the neuropsychological deficits in alcoholics, 50 problem drinkers (25 drinkers under the age of 40 and 25 drinkers 40 y
A recent article in the Cincinnati Enquirer reported that the mean labor cost to repair a heat pump is $90 with a standard deviation of $22. Monte's Plumbing and Heating Service completed repairs on two heat pumps this morning. The labor cost for the first was $75 and it was $100 for the second. Compute z values for each and com
In Lee County Georgia the distribution of weekly wages for workers in the construction industry is skewed to the right with mean equal to $473 (Georgia Department of Labor, Labor Market Information, 1999). Assume the standard deviation of the distribution is $25. An economist plans to randomly sample 40 workers in Lee County and
A recent study by the Greater Los Angeles Taxi Drivers Association showed that the mean fare charged for service from Hermosa Beach to the Los Angeles International Airport is $18.00 and the standard deviation is $3.50. We select a sample of 15 fares. A. What is the likelihood that the sample mean is between $17.00 and $2
1. Given A,B,C,D as standard normals, find the probability distribution of AB-CD.
What is the value of a European call option on a futures contract when the futures contract price is $20, the strike price is $20, the risk free interest rate is 10% per annum, the volatility is 40% per annum, and the time to maturity is one year.
(See attached file for full problem description) Let , i=1, 2, ...,m be a simple regression, where xi unobservable and assumed to be independent and identically distributed with common distribution Instead, we assume that, for each xi, zi1, zi2, . . . , zin are observed. Given xi, the conditional distribution for the obs
Please see the attached document for the questions.
Assume that the mean hourly cost to operate a commercial airplane follows the normal distribution with a mean $2100 per hour and a standard deviation of $250. What is the operating cost for the lowest 3 percent of the airplanes?
Suppose that a researcher found that the people living in a particular city have a mean score of 40 and a standard deviation of 5 on a measure of concern about the environment. Assume that their concern scores are normally distributed. Approximately what percentage of people in this city have a score (a) above 40, (b) above 45,
The Fitness Shop is considering ordering a special model exercise machine. Each unit will cost the shop $220 and it will sell for $400. Any units not sold at the regular price will be sold at the year-end model clearance for $150. Assume that demand follows a normal probability distribution with µ = 10 and variance = 3. What is
A graduate school program in Engineering will admit only students with GRE math proficiency score in the top 20. National GRE math scores are normally distributed with the mean of 547 and the standard deviation of 105. What is the lowest GRE score math they will accept? Please answer in MS Word.
54. Suppose the sediment density (g/cm) of a randomly selected specimen from a certain region is normally distributed with mean 2.65 and standard deviation .85 (suggested in "Modeling Sediment and Water Column Interactions for Hydrophobic Pollutants," Water Research, 1984: 1169?1174). a. If a random sample of 25 specimens is