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No. & Date AskedQuestion
# 913 :: 12/5/11
Question 913 has been Answered
The mean is 112 oz, and the standard deviation is 40 oz. Compute the probability that the mean from a sample of 49 will fall between 103 and 121 oz. . .

Z-Score, Area between, Standard Error of the Mean

# 897 :: 7/27/11
Question 897 has been Answered
What is the probability for the following values of Z? a. Z < 1.35 b. Z > -1.84 and Z < 2.52 c. Z < 1.02 and Z > 2.77. . .

Area between, Z-Score

# 894 :: 7/17/11
Question 894 has been Answered
Can percentages be converted to z score?. . .

Z-Score

# 870 :: 11/6/10
Question 870 has been Answered
A hospital in California uses 100.6 degrees Fahrenheit as the lowest temperature considered to indicate a fever. What percentage of normal and health. . .

Z-Score

# 824 :: 11/8/09
Question 824 has been Answered
The grades on a statistics midterm test are normally distributed with a mean of 78 and a standard deviation of 6 a. What proportion of the class has . . .

Z-Score, Standard Error of the Mean

# 815 :: 10/5/09
Question 815 has been Answered
Shaver Manufacturing, Inc., offers dental insurance to its employees. A recent study by the human resource director shows the annual cost per employee. . .

Z-Score, Area between

# 813 :: 10/2/09
Question 813 has been Answered
Serum cholesterol levels were taken from a population of 10,000 college students. The results were normally distributed. Males had a mean of 195 and a. . .

Z-Score, NORMSDIST

# 804 :: 8/29/09
Question 804 has been Answered
The mean on this test is 3.5 with a standard deviation of .5. Sally scores 1.5 on this test. How many standard deviations is Sally from the mean?. . .

Z-Score

# 794 :: 8/10/09
Question 794 has been Answered
A psychologist has developed a test to measure self-control. The test is normed so that it has a mean of 100 and a standard deviation of 15... The s. . .

Z-Score, Percent Score, Percentile Rank, Area between

# 793 :: 8/8/09
Question 793 has been Answered
For the total population of a large southern city, mean family income is $34000, with a standard deviation (for the population) of $5000. a. imagi. . .

Z-Score

# 791 :: 8/4/09
Question 791 has been Answered
Serum cholesterol levels were taken from a population of 10,000 college students. The results were normally distributed. Males had a mean of 195 and a. . .

Z-Score

# 767 :: 6/24/09
Question 767 has been Answered
IQ scores are normally distributed with a mean of 100 and a std dev of 15. If 25 people are randomly selected for an IQ test, find the probably that . . .

Z-Score

# 739 :: 6/4/09
Question 739 has been Answered
How many data do we need as a minimum in order to calculate the z-score meaningfully?. . .

Z-Score

# 718 :: 5/5/09
Question 718 has been Answered
The state of Texas college admission board has set a standard for automatic acceptances to any university at top 10% of any graduating class will be a. . .

Z-Score

# 716 :: 5/5/09
Question 716 has been Answered
The rockets are playing Lakers tonight in basketball. The lakers average 90 points a game, with a SD of 10. What would the rockets need to score to be. . .

Z-Score

# 715 :: 5/5/09
Question 715 has been Answered
university of texas will accept all students that have a GPA in the top 10% at their school. At yates the school GPA average is 3.0(on a 4.0 scale) wi. . .

Z-Score

# 714 :: 5/5/09
Question 714 has been Answered
The mean score on a math test at milby high school was 50. the standard deviation was 10. If the same test was administered to the entire school distr. . .

Z-Score

# 708 :: 4/30/09
Question 708 has been Answered
Standardized scores offers a way of comparing norm-referenced scores. The z-score distribution is based on knowing how many standard deviations away f. . .

Z-Score, t-score, Percentile Rank

# 702 :: 4/26/09
Question 702 has been Answered
A random sample of 100 students who took a statistics exam were asked their score on the exam. The mean score on the test was 50; the standard deviat. . .

Z-Score, Area between

# 644 :: 3/3/09
Question 644 has been Answered
An aptitude test has a mean of 220 and standard deviation of 10. find the corresponding z score for: a) a test score of 232 b) a test score of 212. . .

Z-Score

# 621 :: 2/8/09
Question 621 has been Answered
Consider a sample with data values of 10,20,12,17, and 16. Compute the z-score for each of the five observations. . .

Z-Score

# 618 :: 2/8/09
Question 618 has been Answered
Individual scores of a placement examination are normally distributed with a mean of 84.2 and a standard deviation of 12.8. If a random sample of s. . .

Z-Score, t-score

# 613 :: 2/7/09
Question 613 has been Answered
I am confused on how to calculate a z-score. I am doing a six sigma project right now and am lost on doing the z-score. Here is the information I am p. . .

Z-Score

# 599 :: 1/30/09
Question 599 has been Answered
There are two major tests of readiness for college, the ACT and the SAT. ACT scores are reported on a scale from 1 to 36. The distribution of ACT scor. . .

Z-Score, SAT Scores, ACT Scores

# 588 :: 1/26/09
Question 588 has been Answered
An aptitude test has a mean of 220 and standard deviation of 10. find the corresponding z score for: a) a test score of 232. . .

Z-Score

# 572 :: 1/13/09
Question 572 has been Answered
At one university, students are given z-scores at the end of the semester rather than the traditional GPAs. The mean and standard deviation of all stu. . .

Empirical Rule, Z-Score

# 571 :: 1/10/09
Question 571 has been Answered
Dr Zak developed a test to measure depression. He sampled 100 university students to take his five item test. The group of students was comprised of 3. . .

Z-Score, Standard Score

# 559 :: 12/16/08
Question 559 has been Answered
The serum cholesterol levels for men in one age group are normally distributed with a mean of 185.1 and a standard deviation of 37.8. All units are i. . .

Area between, Z-Score

# 558 :: 12/16/08
Question 558 has been Answered
If Z is a standard normal variable, find the probability that z lies between 0.73 and 1.88 or P(0.73

Area between, Z-Score

# 530 :: 12/2/08
Question 530 has been Answered
What score would it have taken to be in the 90th percentile in a test with a mean of 40 and standard deviation of 7. . .

Z-Score, Percent Score

# 524 :: 11/24/08
Question 524 has been Answered
Discuss how t test can be employed in hypothesis testing by the use of directional vs. nondirectional hypotheses. Discuss types of research where usi. . .

t-score, Z-Score, directional test, nondirectional test, 1-Sided Test

# 517 :: 11/22/08
Question 517 has been Answered
An executive drives his vehicle from home to work daily. Driving times are normally distributed with a mean of 35 minutes and standard deviation of 8. . .

Z-Score, Area between, above .10

# 516 :: 11/19/08
Question 516 has been Answered
Given a mean score of 70, standard deviation of 15,percentile of 23.Find the Z score,T score and raw score. Please explain how to work backward on a . . .

T score, Percent Score, Z-Score

# 502 :: 11/7/08
Question 502 has been Answered
Administrative staff based at a business school in the UK are advised to take a 15 minute break from their personal computer after working on it for 9. . .

Confidence Intervals, TDIST, t-test, Z-Score

# 500 :: 11/7/08
Question 500 has been Answered
In a recent year grade 8 Washington State public school students taking a mathematics assessment test had a mean score of 276.1 with a standard deviat. . .

Percent Score, Area between, Z-Score

# 494 :: 11/4/08
Question 494 has been Answered
If the average price of a new home is 145,000 what is the minimum and maximum prices of the houses a contractor will need to build to include the midd. . .

Z-Score, Area between

# 493 :: 11/4/08
Question 493 has been Answered
On a police sergeants exam, the historical mean scored was 80 with a standard deviation of 20. Four offiers scored 195,175,191, and 189 respectively. . . .

Empirical Rule, Z-Score, Unusual Event, Percent Score

# 484 :: 10/25/08
Question 484 has been Answered
With a normal distribution of 50 and standard deviation of population =10, how do I figure out the score at the 40th percentile? How do I figure out t. . .

Z-Score, Area between, Percent Score

# 476 :: 10/13/08
Question 476 has been Answered
Does normal distribution is something to do with Altman Z-Score?. . .

Altman Z-Score, Z-Score

# 464 :: 10/7/08
Question 464 has been Answered
How do you know when to use a t-score instead of a z-score and vice versa?. . .

Z-Score, t-score

# 462 :: 10/6/08
Question 462 has been Answered
Olympic Track related question: You know the last 5 race times at the same distance for 8 runners competing in a race. As such, you can calculate the. . .

Z-Score

# 459 :: 10/5/08
Question 459 has been Answered
How do you calculate a participant score if she was at the 67th percentile? I only have the standard deviation of the population and the mean. s = 27 . . .

Percent Score, Percentile, Z-Score

# 428 :: 9/29/08
Question 428 has been Answered
Each student in an experiment was told to look at 100 cars and count the number of people wearing the seat belts. The mean score for the class was fou. . .

Z-Score

# 423 :: 9/28/08
Question 423 has been Answered
the lengths of human pregnancies are normally distributed with a mean of 268 days and a standard deviation of 15 days. What is the probability that a . . .

Z-Score

# 420 :: 9/28/08
Question 420 has been Answered
In one region, the September energy consumption levels for single-family homes are found to be normally distributed with a mean of 1050 kWh and a stan. . .

Z-Score

# 417 :: 9/27/08
Question 417 has been Answered
Could you detail the value of using standard scores (Z scores) to compare relative performance of individual test scores.. . .

Z-Score

# 409 :: 9/24/08
Question 409 has been Answered
What is the height of a man with the z score of -1.7?. . .

Z-Score

# 401 :: 9/20/08
Question 401 has been Answered
A woman wrote to DearAbby and claimed that she gave birth 308 days after a visit from her husband, who is in the Navy. Lengths of pregnancies have a . . .

Z-Score, Unusual Event

# 397 :: 9/19/08
Question 397 has been Answered
mean score 100,standard deviation 20, z score-5 , what is the raw score?. . .

Z-Score, Raw Score from Z-score

# 390 :: 9/18/08
Question 390 has been Answered
How do you find the normal distribution when the mean is 50 witha standard deviation between scores of 32 and 47?. . .

Area between, Z-Score

# 389 :: 9/18/08
Question 389 has been Answered
How do you dertermine a z-score for continuous data?. . .

Z-Score

# 385 :: 9/16/08
Question 385 has been Answered
Given that the traveling distance for a population of college students is normally distributed with the mean of 10 kilometers and standard deviation e. . .

Z-Score

# 381 :: 9/13/08
Question 381 has been Answered
If I know the T-score for those who made an A on a test is 60, the z-score for those that made a B is .5, the number of students total is 200, how can. . .

Z-Score

# 379 :: 9/11/08
Question 379 has been Answered
1 a. with a mean of 300 and a standard deviation of 80, how high a score do you need to be in the top 30%? 1 b. What is the interquartile range for. . .

Interquartile Range, Z-Score

# 378 :: 9/10/08
Question 378 has been Answered
We have administered an anxiety test to all members of the class. The mean anxiety score is 71 and the standard deviation is 9. (higher score=higher a. . .

Z-Score

# 370 :: 9/6/08
Question 370 has been Answered
The accounting department at Weston reports that it takes two construction workers a mean of 32 hours and a standard deviation of 2 hours... Determin. . .

Area between, Z-Score

# 367 :: 9/5/08
Question 367 has been Answered
find the area under standard normal curve which lies (a) to the right of Z=1.76,(b)to the left of Z=.94,(c)to the right of Z=-.65,(d)b/w Z=.34 & Z=.62. . .

Area between, Z-Score

# 358 :: 8/25/08
Question 358 has been Answered
In the same set of data,can two or more elements have the same z score.. . .

Z-Score

# 356 :: 8/24/08
Question 356 has been Answered
The mean weight of 500 students is 151 lbs and the standard deviation is 15 lbs. Assuming the weights are normally distributed, find out how many stu. . .

Area between, Z-Score

# 349 :: 8/15/08
Question 349 has been Answered
A bank has determined that the monthly balances of savings accounts of its customers are normaly distributed with an average balance of $1200 and stan. . .

Z-Score

# 348 :: 8/15/08
Question 348 has been Answered
A random variable X is normal distributed with a mean of 250 and standard deviation of 50. Given that X = 175, what is its corresponding z-score? Rou. . .

Z-Score

# 334 :: 8/10/08
Question 334 has been Answered
find the z value so that 20% of the standard normal curve lies to the right of Z. . .

Z-Score

# 333 :: 8/10/08
Question 333 has been Answered
A woman sells an average of 300 books per month, with a standard deviation of 50. Over the next ten years, how many months will she sell more than 375. . .

Z-Score

# 318 :: 8/6/08
Question 318 has been Answered
A traffic study at one point on an interstate highway shows that vehicle speeds are normally distributed with a mean of 61.3 mph and a standard deviat. . .

Area between, Z-Score

# 299 :: 7/30/08
Question 299 has been Answered
random variable x is normally distributed with mean of 250 and standard deviation of 50 find z-score for x=175. . .

Z-Score

# 295 :: 7/28/08
Question 295 has been Answered
How can I calculate a Z score with only the mean and the standard deviation?. . .

Z-Score

# 294 :: 7/28/08
Question 294 has been Answered
A test is normally distributed with a mean of 40 and a standard deviation of 7. (a) What score would be needed to be in the 85th percentile?. . .

Z-Score, Percentile, Percentile Rank

# 293 :: 7/28/08
Question 293 has been Answered
How can you use a Z score to interpret data in a school. . .

Z-Score

# 289 :: 7/25/08
Question 289 has been Answered
A standard I.Q. test produces normally distributed results with a mean of 100 and a standard deviation of 15. If an average I.Q. is defined to be any . . .

Z-Score, IQ Score

# 283 :: 7/19/08
Question 283 has been Answered
The lengths of pregnancies are normally distributed with a mean of 264 days and a standard deviation of 25 days. If 100 women are randomly selected, f. . .

Z-Score, Area between

# 277 :: 7/14/08
Question 277 has been Answered
If an A is given to a student who scores 90% or above, what would the minimum z-score be for a 300 multiple choice question test with a mean of 195 an. . .

Z-Score

# 275 :: 7/11/08
Question 275 has been Answered
The lowest 25% of the normal distribution falls below what z-score and t-score. . .

T score, Z-Score

# 269 :: 7/9/08
Question 269 has been Answered
A classical experiment in extrasensory perception (ESP) consists of asking a subject to tell, without looking, the suit of each card in a deck of Zene. . .

Z-Score, Binomial Probability, Normal Approximation, binomial, BINOMDIST

# 262 :: 7/3/08
Question 262 has been Answered
with a mean of 150 and a standard deviation of 15 what is the probability of a student having a weight of less than 178 lbs.. . .

Z-Score

# 260 :: 7/1/08
Question 260 has been Answered
Suppose that the scores of architects on a particular creativity test are normally distributed. What percentage of architects have Z scores (a) above . . .

Z-Score

# 253 :: 6/26/08
Question 253 has been Answered
What are the 2 advantages of using Z power? If the z score is less than 0, what can be said of the corresponding raw score? If the z score is great. . .

Z-Score

# 249 :: 6/24/08
Question 249 has been Answered
A nationally standardized test is scaled so that the normally distributed scores have a mean of 80 and a standard deviation of 10 in the population. I. . .

Z-Score

# 247 :: 6/24/08
Question 247 has been Answered
Jeff: Can you possibly share the actual formula you are using in this application to produce the Adjusted Wald calculations? Thanks. . .

Adjusted Wald, Z-Score, Confidence Intervals

# 239 :: 6/16/08
Question 239 has been Answered
I have a data set where n=20. My problem is to find the score at exactly the 75th percentile assuming normality. I know the formula for z-score, the. . .

Z-Score

# 233 :: 6/13/08
Question 233 has been Answered
Between what two values of Z will 88% of the middle data values fall between?. . .

Z-Score

# 232 :: 6/12/08
Question 232 has been Answered
If a distribution of test scores is normal with a mean of 78 and a standard deviation of 11, what percent of the area lies below 60. . .

Z-Score

# 230 :: 6/11/08
Question 230 has been Answered
a score that is 8 points above the mean corresponds to a z-score=0.05 What is the population standard deviation?. . .

Standard Deviation, Z-Score

# 219 :: 6/6/08
Question 219 has been Answered
A z score of 1.04 shows a percentage value of?. . .

Z-Score

# 210 :: 5/29/08
Question 210 has been Answered
My local coffee house sells Colombian coffee beans to supermarkets in bags labelled 100g each. The tolerance of the automatic filling machine, lead. . .

Z-Score

# 207 :: 5/24/08
Question 207 has been Answered
Suppose that the scores of architects on a particular creativity test are normally distributed.What percentage of architects have Z scores. (a) abov. . .

Z-Score

# 206 :: 5/24/08
Question 206 has been Answered
The variable Z has a standard Normal distribution. a) Find the number z that has cumulative proportion 0.85. b) Find the number z such that the eve. . .

Z-Score

# 205 :: 5/22/08
Question 205 has been Answered
Find the number z that has cumulative proportion 0.8. . .

Z-Score

# 204 :: 5/22/08
Question 204 has been Answered
What does a z value mean?. . .

Z-Score, Z-value, Standard Score

# 202 :: 5/21/08
Question 202 has been Answered
Site preparation for new housing developments for tracts of 40 houses is normally distributed with a mean of 250 workdays and a standard deviation of . . .

Z-Score

# 186 :: 5/9/08
Question 186 has been Answered
how does altman build z-score? please send to my email the process of building this score!. . .

Altman Z-Score, Z-Score

# 177 :: 5/2/08
Question 177 has been Answered
Find the probability that a randomly selected adult has an IQ that is less than 130. . .

IQ Score, Z-Score

# 176 :: 4/30/08
Question 176 has been Answered
In a 0ne-tail test (l side) with z score of 1.645, what are the percentages for critical value and non-critical value?. . .

One-Tailed Area, Z-Score, Critical Value

# 173 :: 4/27/08
Question 173 has been Answered
why can you not have a z- score equaling 0/0 ? what is problematic with calcutlating a z-score for a data set of repeated entries?. . .

Z-Score

# 170 :: 4/25/08
Question 170 has been Answered
If last six month average defect rate is 5% then what will be the process Zst score? . . .

1.5 Sigma Shift, Z-Score, Z Short Term

# 161 :: 4/21/08
Question 161 has been Answered
z Scores lenths are measured in centameters, does it have to be converted to a different unit of measurment? . . .

Z-Score

# 157 :: 4/17/08
Question 157 has been Answered
With a z score of 1.5, what percentage often scores are above 52 and what percentage of the scores are above 60?. . .

Z-Score

# 146 :: 4/9/08
Question 146 has been Answered
what is the z-score that corresponds to the 20th percentile of the normal distribution. . .

Z-Score, Percentile

# 137 :: 4/4/08
Question 137 has been Answered
What score would Sandra need to beat 91 percent of her mathematics class? The mean score was 73, and the standard deviation was 12.. . .

Z-Score

# 135 :: 3/31/08
Question 135 has been Answered
I am conducting a ring test where 6 laboratories were asked to measure protein levels in the same flour sample. I then calculated the z score for each. . .

Z-Score

# 128 :: 3/25/08
Question 128 has been Answered
What is the value of z score required for a 70% confidence interval?. . .

Z-Score, , Confidence Intervals

# 114 :: 3/16/08
Question 114 has been Answered
The mean on this test is 3.5 with a standard deviation of .5. Billy scores 5. What is the standard score?. . .

Standard Score, Z-Score

# 96 :: 3/1/08
Question 96 has been Answered
The mean is ž = 60.0 and the standard deviation is ů = 4.0. Find the probability that X is less than 53.0.. . .

Z-Score

# 70 :: 12/10/07
Question 70 has been Answered
The grades on the midterm given in a large managerial stats class are normally distibuted with mean 75 and standard deviation 9. Instructors of this c. . .

Z-Score, Percentile

# 48 :: 10/29/07
Question 48 has been Answered
Suppose that the scores of architects on a particular creativity test are normally distributed. What percentage of architects have Z scores? a. above . . .

Z-Score

# 42 :: 10/29/07
Question 42 has been Answered
What are the units of z-score?. . .

Z-Score, Units of Measure

# 41 :: 10/29/07
Question 41 has been Answered
On a scale from 0 to 100, the mean level of economic development among the countries in the world is 65 and the standard deviation is 10. What proport. . .

Z-Score, Standard Normal Curve

# 39 :: 10/29/07
Question 39 has been Answered
What is the basic formula for the z-score other than table of areas?. . .

Newton-Raphson, Z-Score

# 38 :: 10/29/07
Question 38 has been Answered
Alexa got 144 on her test which has a mean of 128 and a standard deviation of 34. What is her z-score?. . .

Z-Score, example

# 37 :: 10/29/07
Question 37 has been Answered
How do you calculate the z score for the raw score of 10 based on the following distribution: 8, 9, 15, 30, 7, 8 ?. . .

Z-Score, Standard Deviation

# 33 :: 10/29/07
Question 33 has been Answered
How do you find a z score such that 8% of the area under the curve is to the right of Z?. . .

Z-Score, One-Sided Area

# 29 :: 10/29/07
Question 29 has been Answered
How do you calculate a z-score on discrete data?. . .

Z-Score, Discrete Data

# 26 :: 10/29/07
Question 26 has been Answered
How do you calculate z-scores from batting averages?. . .

Z-Score

# 25 :: 10/29/07
Question 25 has been Answered
What does a Z-score look like on a graph?. . .

Z-Score

# 17 :: 10/29/07
Question 17 has been Answered
Having obtained the z score and then derived the percentage... what does the percentage tell you?. . .

Unusual Event, Z-Score

# 15 :: 10/23/07
Question 15 has been Answered
How do you calculate a Z-score with a two-sided specification limit? What is the DPMO?
I have a lower spec limit of -0.008 and an uppers spec lim. . .

DPMO, Z-Score, Process Sigma, Z-upper

# 14 :: 10/23/07
Question 14 has been Answered
What percent of the time should this occur? (Z-Score) ?. . .

Z-Score, Normally Distributed, Standard Deviation, Normal Curve

# 13 :: 10/23/07
Question 13 has been Answered
How unusual is this event (Z-Score)? A department store, on average, has daily sales of $28,707.47. The standard deviation of sales is $1000. . . .

Z-Score, Unusual Event

# 12 :: 10/23/07
Question 12 has been Answered
Can a z score be calculated by input of a proportion only?. . .

Proportion, Z-Score

# 11 :: 10/23/07
Question 11 has been Answered
What is the z value for 1.648?. . .

Z-Score

# 10 :: 10/23/07
Question 10 has been Answered
What is the difference between a Z-Scores and Process Sigma?. . .

Process Sigma, Z-Score, 1.5 Sigma Shift

# 4 :: 10/23/07
Question 4 has been Answered
Where can I find a Z score chart ?. . .

Z-Score

# 3 :: 10/23/07
Question 3 has been Answered
What is the critical z score for a one tailed test with alpha = .01.. . .

Alpha, Z-Score

# 2 :: 10/23/07
Question 2 has been Answered
Joe received a z score of -1.50 on a classroom test. This means that, compared to his classmates, Joe's score was...?. . .

Z-Score, 1.5, lambda