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Dispersion and Spread of Data

Standard Deviation

With a height of 63 in Adams was the shortest president of a particular sports clubs in the past century. The sports club president of the century has a mean height of 71.7 in and a standard deviation of 2.4 A. What is the difference between Adam's height and mean? B. How many standard deviations is that [the difference

Payne (2001) Gave Participants a Computerized Task - Mean and Standard Deviation

Payne (2001) gave participants a computerized task in which they first see a face and then a picture of either a gun or a tool. The task was to press one button if it was a tool and a different one if it was a gun. Unknown to the participants while they were doing the study, the faces served as a "prime" (something that starts y

Formula to complete problem

I simply need help with setting up the formula or an example of how to complete the problem on my own. I have been reading the topics but nothing explained what formula to use to get the answer so can someone please show me the steps so I can compute it myself. 1.) The distribution of weights for a sample of 1,400 cargo co

Standard Deviation for Psychology Exam

For a particular sample of 50 scores on a psychology exam, the following results were obtained. First quartile = 67 Third quartile = 91 Standard deviation = 9 Range = 48 Mean = 75 Median = 80 Mode = 81 Midrange = 74 a)What score was earned by more students than any other score? Why? b)How many students scored b

Summation Notation, Percentile and Proportion

Please show your work. I am having trouble working out the problems. I would like as detailed an explaination for the answers as you can give. 1. A teacher gives a 20-point quiz to 10 students. The scores are listed below. What percentile corresponds to the score of 12? 20 8 10 7 15 16 12 19 14 9 A. 13 B. 40 C.

Discussing Population Standard Deviation

A moose claims that the average time he spends grazing per day is 6.8. Test his claim at the a=.05 level. A random sample of 234 moose shows they spent an average of 6.1 hours per day grazing. The population standard deviation is known to be 2.3 hours. What do you conclude about the claim?

Standard Deviation

Q3. A manufacturer of automobile battieries claims that hte distribution of the lenghts of life of its best bateries has a mean of 54 months and a standard deviation of 6 months. Suppose a consumer group decides to check the manufacturer's claim by purchasing a sample of 50 of those batteries. a) assuming that manufacturer's cl

Basic Statistics and Bar Graphs

1. Find the first and third quartiles, Q1 and Q3, of the following set of numbers. 0.16, 0.08, 0.27, 0.20, 0.22, 0.32, 0.25, 0.18, 0.28, 0.27 a. 0.16; 0.28 b. 0.18; 0.27 c. 0.16; 0.27 d. 0.18; 0.28 2. Continent or Region Land Area (1,000 mi2) % of Earth Population 1900 Population 1950 Population 2000 North Am

Development of a Test to Measure Depression

Dr. Zak Case Study INSTRUCTIONS Read the following case study. Then, use the information in the case study to answer the accompanying follow-up questions. Although questions 1-2 have short answers, you should prepare a 150 to 200-word response to each of the remaining questions. CASE STUDY Dr. Zak developed a test to measure

15 Problems : Five-Number Summary, GCF, Factorization, Perimeter and Area

4. Jamal is fencing a rectangular field that measures 40 ft by 15 ft. How much fencing should he buy? 7. Find the prime factorization of the number 360. 8. Find the greatest common factor of 16, 12, and 100. 13. Find the least common multiple of 15 and 21. 18. Jacque earns $9.60 per hour (h). For overtime (each h

Normal Distribution: First Mortgage

The average conventional first mortgage for new single-family homes was $294,000. Assuming a normal distribution and a standard deviation of o = $30,000, what proportion of the mortgages were: a. more than $294,000? b. between $234,000 and $354,000? c. between $264,000 and $342,000? d. more than $204,000?

Time Measurement and Histogram Construction

1. A psychologist is studying the length of time it takes mice to go through a maze and reach a reward at the end. Time is measured to the nearest tenth of a second with the results given in the table below. Time Frequency 2.0 up to 3.0 3 3.0 up to 4.0 7 4.0 up to 5.0 15 5.0 up to 6.0 29 6.0 up to 7.0 81 7.0 up to 8.0

Statisitics: Mean, Median, Mode and Pie Charts

Please see the attached file for the fully formatted problems. 1. Find the mean of the following set of numbers. 13, 15, 18, 18, 18, 19, 22, 26, 28, 33 2. Find the median of the following set of numbers. 24, 26, 31, 33, 35, 36 3. Find the mode of the following set of numbers. 22, 55, 43, 26, 33, 36, 43, 2

Age Distribution of Prehistoric Native Americans

This is a 3 step problem requested as an example however we have not gone over how to do this yet, I need help with understanding these steps. I have a chart with the greek letters and numbers but am not sure how to put this in order. It is requested to answer and show work so whatever help you may offer will help me better unde

Mean and standard deviation

A test consists of 10 multiple choice questions, each with 5 possible answers, only one of which is correct. Assume that test participants guess at the answers. Find the mean and standard deviation of the number of correct answers

Predicting Mean and Standard Deviation

If the sampled population has a mean of 48 and a standard deviation of 16, then the mean and the standard deviation for the sampling distribution of x -bar for n = 16 is?

Basic statistics: mean, variance and standard deviation

1. Plywood, Inc. reported these returns on stockholder equity for the past 5 years: 4.3, 4.9, 7.2, 6.7, and 11.6. Consider these as population values. a. Compute the range, the arithmetic mean, the variance, and the standard deviation. 2. The annual incomes of the five vice presidents of TMV Industries are: $125,000; $128,0

Expected Value and Standard Error

For a sample selected from a population with a mean of u=50 and a standard deviation of o=10: what is the expected value of M and the Standard error of M for a sample of n=4 scores?

Prime numbers, fractions, etc

(See attachment for details) 11 A baseball player scored a total of 27 runs in the first 20 games of the season. If he continues at the same pace, how many runs should he score in the 80-game season? Show Work Below 12 Estimate the result in the following division problem. (Remember to round divisors to the neares


Given the following data set, find the value that corresponds to the 75th percentile. 10, 44, 15, 23, 14, 18, 72, 56

Standard Diviation

-1, 0, 2, 3, 7, 10, 10 The standard deviation of the data above is (to the nearest 1/10) a. 5.0 b. 5.3 c. 6.3 d. answer not listed

Critical value and standard deviation

Please see the attached file. Determine the 2 chi-squared critical values for the following confidence levels and sample sizes. We are also interested in estimating the variation for the PDA selling prices through examination of the standard deviation, sigma (σ). We will again assume that selling prices are clo

Graphing and Basic Statistics

Please see the attached for the math questions I need help with. 1. The following table gives the population of certain states according to the 2000 census. State Population Illinois 12,419,293 New Jersey 8,414,350 New York 18,976,457 Tennessee 5,689,283 Texas 20,851,820 Construct a bar graph from this informat

Standard Deviation and Expected Value

You are in charge of an experiment to evaluate a treatment which is advertised as being 90% effective at killing a particular insect. You plan an experiment in which the treatment is tested on 200 insects. a. If the advertising is accurate, what is the expected value and standard deviation of the number of insects that ought

Mean and Standard Deviations

A component is comprised of two halves. The thickness of each half is normally distributed with a mean of 2 millimeters and a standard deviation of 0.1 millimeter and the halves are independent. a. Determine the mean and standard deviation of total thickness of the two halves. Answer E(T)=4 , and sigma of T=0.1414 ? b. What