25 articles trouvés pour ce sujet.
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15 films |
1999-11-09 |
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Hebert pose la question : Un touriste revient de vacnces avec 15 films: - 2 films de photos d 'Italie
- 8 films de photos de Grèce
- 5 films de photos de Turquie.
Aucune marque distinctive ne permet d'identifier les films. Pour des raisons financières le touriste ne fait développer à son retour que 11 de ces 15 films qu'il choisit au hasard.NB : on donnera les résultats sous forme décimale approchée à 10-4 près. - Combien y a t il de choix différents possibles de 11 films parmi les 15 ?
- Quelle est la probabilité que , parmi les 11 films développés, il y ait:
- ...
Claude Tardif lui répond. |
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The range of a set of numbers |
2008-11-19 |
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krista pose la question : hi, i was working on a math problem for homework and it asked me to
find the range out of these numbers:
1,15,16,16,19,25,27,28,28, can you help me? Penny Nom lui répond. |
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Outliers in a box and whisker plot |
2006-02-19 |
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A student pose la question : i need help on determining if their is an outlier...i know how to find the median and the lower quartile and the upper quartile..but i don't understand about the outliers....please tell me if their is an outlier in this problem....the numbers are...63,88,89,89,95,98,99,99,100,100 Penny Nom lui répond. |
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The range of a data set |
2005-10-04 |
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Carmen pose la question : What is the range of this data? 36,64,37,45,53,60. Penny Nom lui répond. |
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On which assignment did I do better |
2002-05-17 |
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Denise pose la question : I have 2 writing assignments in class. The first assignment, which had a mean of 10 and a standard deviation of 2, I got a score of 12. The second assignment had a mean of 18 and an s.d. of 3, I got a 21. I need to know which assignment did I do better, relative to my classmates? Andrei Volodin lui répond. |
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The Dugout, Don's Basement, Cd Corner,... |
2002-04-30 |
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A student pose la question : The Dugout, Don's Basement, Cd Corner, Harry's Deli, Bill's Software, Anne's Footwear, and Joanne's House cleaning. The gift certificates are each in multiples of $5. There is a $100 range in the value of the gift certificates, which start at $25. The mean value of all seven gift certificates is $80, and the median and mode are both $70. The certificate from The Dugout is worth the most and the one from Joanne House cleaning is worth the least. The total value of the gift certificates from CD Corner, Harry's Deli, and Anne's Footwear is $270, but Anne's Footwear certificate is worth $50 more than the one from Harry's Deli. The Cd Corner gift certificate is equivalent to the mean for this group of three. What is the value of the gift certificates from each store? Penny Nom lui répond. |
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Range of values for standard deviation |
2002-03-22 |
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Susan pose la question : What is the range of values for standard deviation? Is it between 0 and +3? Is it between +1 and +3? Andrei Volodin lui répond. |
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Testing a hypothesis |
2002-03-14 |
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A student pose la question : A large distriutor of cosmetics has kept his outstanding accounts receivable to a mean age of 18 days over the past year. This average is considered a standard by which to measure the efficiency of the credit and collections department. Management wishes to check if receivables in the current month is over standard and will do this at a significance level of 0.50. A random sample of 100 accounts yields an average of 20 days with a standard deviation of 9 days. what should management conclude? Andrei Volodin lui répond. |
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The median with ties |
2002-02-27 |
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Marcel pose la question : What, exactly, is the proper way to determine the median of a set of numbers when doubles or triples of a number are part of that set? Do the doubles count as two and the triples three, or does each count only as one toward determining the median. Harley Wston lui répond. |
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Column doesn't add up to 100% |
2001-10-17 |
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A student pose la question : why don't some tables I'm studying in a column add up to 100%? Example: N=338, but responses to questions asked in survey I'm studying equal of 24.3, 9.8, 43.8, DON'T add up to 100%. I'm assuming that some people surveyed out of the 338 didn't bother responding, but is there another problem related to proportion or ratio being used, but improperly labeled on graph?. Note at bottom of table says: "number in parenthesis are numbers of cases" and 338 was in parentheses. I'm lost. Penny Nom lui répond. |
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Ciefficient of variation |
2001-09-23 |
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Carmen pose la question : I have a question from my OAC finite class. I've come across a problem with the coefficient of variation. I have taught my students that there are no units for coefficient of variation and it can be expressed as a percent. So, for example, a set of data with mean of 5 and standard deviation of 100 would have a CV of 5%. But what happens in this situation: the mean is 4meters and the standard deviation is 0.7mm. Is the CV 1.75% or 0.00175% or 0.0175%? I've had some students change leave the units as is, change them both to mm or change them both to meters...so which is it and why? Penny Nom lui répond. |
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Double bar graphs |
2001-09-09 |
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Leslie pose la question : My daughter has a homework problem in which she is graphing data from two frequency tables onto a double bar graph. The graph shows how many students worked in a program in two different years, grouped by age. In the first age group, one of the years has no students working, while there were students in that age group in the other year. Penny Nom lui répond. |
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A confidence interval |
2001-06-28 |
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Murray pose la question : An investigator wants to find out of there are any difference in "skills" between full and part time students. Records show the following:
Student Mean Score Std Dev Number
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Full time 83 12 45
Part time 70 15 55
Compute a 95% confidence interval for the difference in mean scores. Andrei Volodin lui répond. |
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What is the difference between Mean and Average? |
2000-12-13 |
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Julie pose la question : What is the difference between Mean and Average? My thinking is the average, is the equal to the sum of all numbers divided by the number of numbers added together. But the mean, I think should be calculated by adding the largest and smallest numbers in the set and them dividing by 2. (which is the point where 1/2 the numbers are higher and 1/2 the numbers are lower) Patrick Maidorn and Penny Nom lui répond. |
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Central Limit Theorem and Law of Large Numbers |
2000-06-26 |
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Jonathan Yam pose la question : The Central limit Theorem states that when sample size tends to infinity, the sample mean will be normally distributed. The Law of Large Number states that when sample size tends to infinity, the sample mean equals to population mean. Is the two statements contradictory? Paul Betts and Harley Weston lui répond. |
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Probability and odds |
2000-05-05 |
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Leah pose la question : The chances of rain on friday, saturday, and sunday are 20%, 30%, and 50% respectively. what are the odds it will rain all three days? Harley Weston lui répond. |
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Box and whisker plots |
2000-03-09 |
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Brett Blake pose la question : Do you have any information on Box and whisker graphs? Harley Weston lui répond. |
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Bar graphs and histograms |
2000-01-11 |
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Raeluck pose la question : What is the difference between a bar graph and a histogram? Harley Weston lui répond. |
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Mean, median and mode |
1999-12-07 |
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J William Morning pose la question : Using the data values 2,2,10,6,5, determine the median, mode and mean. Penny Nom lui répond. |
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Estimating the population mean |
1999-11-13 |
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John Barekman pose la question : Statitistics: Estimating the population mean when the standard deviation is known: I am not sure which n to use in the formula for the confidence interval equation: x +/- z*(standard deviation/sqrt(n)) If we have data of ten people, and if we have the data of ten sets of ten people each, what is the difference in the n that we use? What is the difference between the standard deviation and the standard error? Are we using the number of sampling means or just the number of samples? Harley Weston lui répond. |
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Body part measurements |
1999-11-10 |
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V Bailey pose la question : I am a kindergarten teacher and mother of a 6th grader who wants to do a science project on the correlations of body part measurements. We heard this on the radio and it sparked our interest, but now I cannot find any information about it. Examples are: your height is supposed to equal the distance from fingertip to fingertip when your arms are outstretched. Your foot size is supposed to equal the distance from your wrist to your elbow. Please help me find more information on this topic. Penny Nom lui répond. |
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A pictograph |
1999-10-28 |
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Ali pose la question : Please tell me how to make a pictograph.I am 2 grade student. Penny Nom lui répond. |
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Predictions |
1999-09-22 |
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Joesph Dana pose la question : How do u find the results of an unbiased sample of 100 students that are shown on the table. For example the school has a total of 1,150 students prdict how many students would chose cereal(46) pancakes(15) eggs(20) and sandwich(19) Haeley Weston lui répond. |
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Three dice |
1998-11-17 |
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Ryan Allinson pose la question : Rolling three regular dice how many different ways could a sum of 10 be rolled? Hope you can help. Can you please show me how this is done? Penny Nom lui répond. |
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Rolling a seven |
1998-06-11 |
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Bruce Thompson pose la question : What is the probablity of rolling two dice and it coming out as seven? a) 1/6 b) 1/36 please give me the correct awnser and explain please. Harley Weston lui répond. |
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