EBook Problems Normal Std - Revision history

Tdlee: Text replacement - "{{translate|pageName=http://wiki.stat.ucla.edu/socr/" to ""{{translate|pageName=http://wiki.socr.umich.edu/"

2020-03-03T19:26:04Z

Text replacement - "{{translate|pageName=http://wiki.stat.ucla.edu/socr/" to ""{{translate|pageName=http://wiki.socr.umich.edu/"

2010-02-09T06:04:22Z

added the clarification on the top - some problems come from CLT section of the EBook.

2009-01-06T00:48:07Z

2009-01-04T04:05:23Z

2008-12-19T06:34:47Z

2008-12-19T05:44:47Z

2008-12-19T05:31:51Z

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2008-12-19T01:26:03Z

← Older revision		Revision as of 19:26, 3 March 2020
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	* SOCR Home page: http://www.socr.ucla.edu		* SOCR Home page: http://www.socr.ucla.edu

−	{{translate\|pageName=http://wiki.~~stat~~.~~ucla~~.edu~~/socr~~/index.php/EBook_Problems_Normal_Std}}	+	"{{translate\|pageName=http://wiki.socr.umich.edu/index.php/EBook_Problems_Normal_Std}}

← Older revision		Revision as of 06:04, 9 February 2010
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−	==[[EBook_Problems \| EBook Problems Set]] - [[AP_Statistics_Curriculum_2007_Normal_Std \|The Standard Normal Distribution]]==	+	==[[EBook_Problems \| EBook Problems Set]] - [[AP_Statistics_Curriculum_2007_Normal_Std \|The Standard Normal Distribution]] and [[AP_Statistics_Curriculum_2007_Limits_CLT \| Central Limit Theorem]] Problems==
		+
		+	These problems demonstrate concepts in 2 sections of the [[EBook]] -- [[AP_Statistics_Curriculum_2007_Normal_Std \|The Standard Normal Distribution]] and [[AP_Statistics_Curriculum_2007_Limits_CLT \| The Central Limit Theorem]]. Problems that ask for the distribution (or probabilities) of a single random number, or a sample-average of random numbers, pertain to [[AP_Statistics_Curriculum_2007_Normal_Std \| section on Standard Normal Distribution]], or [[AP_Statistics_Curriculum_2007_Limits_CLT \| section on Central Limit Theorem]], respectively.

	===Problem 1===		===Problem 1===

← Older revision		Revision as of 00:48, 6 January 2009
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	:''(e) About 10%		:''(e) About 10%
	{{hidden\|Answer\|(a)}}		{{hidden\|Answer\|(a)}}
		+
		+	===Problem 21===
		+	Exam Times
		+	Suppose that the distribution of time required for a college student to complete a standardized exam is nearly normal with mean 45 minutes and standard deviation of 5 minutes. If you select 3 students at random, what are the chances that all 3 students finish in less than 35 minutes?
		+
		+	*Choose one answer.
		+
		+	:''(a) Cannot be determined
		+
		+	:''(b) (0.0228)^3
		+
		+	:''(c) 0.0228
		+
		+	:''(d) 3*(0.0228)
		+	{{hidden\|Answer\|(b)}}
		+

@@ Line 263: / Line 263: @@
 :''(d) Can't be answered with the information given
 {{hidden|Answer|(b)}}
 <hr>

← Older revision		Revision as of 06:34, 19 December 2008
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	:''(d) Scott answered at least 80% of the questions correctly		:''(d) Scott answered at least 80% of the questions correctly
		+	{{hidden\|Answer\|(b)}}
		+
		+
		+	===Problem 18===
		+	GSP Inc. is trying two different marketing techniques for its toothpaste. In 20 test cities, it is using family branding. This sells toothpaste with a mean of 2,250 units per week and a standard deviation of 250 units per week. In 20 other test cities, GSP is using individual branding. This sells toothpaste with a mean of 2,250 units per week and a standard deviation of 500 units per week. GSP wants to select the marketing technique that sells at least 2,350 units per week more often. If the number of units sold per week follows a normal distribution, which marketing technique should GSP choose?
		+
		+	*Choose one answer.
		+
		+	:''(a) They each get the same result
		+
		+	:''(b) Individual branding
		+
		+	:''(c) Family branding
		+
		+	:''(d) Can't be answered with the information given
	{{hidden\|Answer\|(b)}}		{{hidden\|Answer\|(b)}}

@@ Line 234: / Line 234: @@
 :''(d) If you pick a person at random, the chance that his IQ falls between 115-130 is less than the chance that his IQ falls between 60-85.
 {{hidden|Answer|(d)}}
 <hr>

@@ Line 220: / Line 220: @@
 :''(d) Smaller than 10 points
 {{hidden|Answer|(a)}}
 <hr>

@@ Line 206: / Line 206: @@
 :''(d) 200
 {{hidden|Answer|(b)}}
 <hr>

@@ Line 151: / Line 151: @@
 {{hidden|Answer|(d)}}
-===Problem 11==
+===Problem 11===
 Fluorescent light bulbs have lifetimes that follow a normal distribution, with an average life of 1,685 days and a standard deviation of 1,356 hours. In the production process the manufacturer draws random samples of 197 lightbulbs and determines the mean lifetime of the sample. What is the standard deviation of this sample mean?
@@ Line 192: / Line 192: @@
 :''(d) It will show a histogram of the Z scores and it will be normal.
 {{hidden|Answer|(a)}}
 <hr>

← Older revision		Revision as of 01:26, 19 December 2008
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	{{hidden\|Answer\|(c)}}		{{hidden\|Answer\|(c)}}

		+	===Problem 13===
		+	If we draw the Normal probability plot for the following histogram, what will it show and how will it appear?
		+
		+	*Choose one answer.
		+
		+	:''(a) It will show the expected cumulative percentiles vs. the actual cumulative percentiles and the points will deviate from a straight diagonal line.
		+
		+	:''(b) It will show the expected cumulative percentiles vs. the actual cumulative percentiles and all the points will approximate a diagonal straight line.
		+
		+	:''(c) It will show a histogram of the Z scores and it will be positively skewed.
		+
		+	:''(d) It will show a histogram of the Z scores and it will be normal.
		+	{{hidden\|Answer\|(a)}}

	<hr>		<hr>