Math 10 Spring 2011 FORM R
Name
Last:______________
First: ____________________
Exam 2:
Chapters 4,5,6,7
Class Time:________________________
DIRECTIONS:
•
Print your NAME and CLASS TIME on THIS EXAM.
•
Print your NAME and CLASS TIME on your SCANTRON.
• Write FORM R on your SCANTRON.
• Each question has exactly one BEST answer.
There are 21 questions.
• You may write on this exam.
There is no scratch paper allowed.
• Each question is worth 5 points for a total of 105 points. This includes 5 bonus points!
• If you have no note page, you must write NO NOTES
on your SCANTRON.
• Put your SCANTRON and PAGE of NOTES inside your EXAM.
Before you start packing up your
things, turn in your EXAM and SCANTRON. Then go back to your desk to pack up your
materials.
When your exam is returned, you will get back all materials you turned in.
• Turn your cell phone OFF.
Any noise from a cell phone will signal that your exam is over.
• FAILURE TO FOLLOW ALL INSTRUCTIONS WILL COST YOU THE 5 BONUS POINTS!
Questions 1  3 refer to the following:
Suppose the time (minutes) Lisa spends grading a Math 10 quiz is uniformly distributed in the interval
(5, 15).
1. Find the mean and standard deviation for the time in minutes Lisa spends grading a math 10 quiz.
A. mean 10, standard deviation 4.33
B. mean 7.5, standard deviation 4.33
C. mean 10, standard deviation 2.89
D. mean 7.5, standard deviation 2.89
2. Find the probability Lisa spends more than 12 minutes grading a math 10 quiz.
A. 12/15
B. 3/15
C. 3/12
D. 3/10
3. If Lisa has already spent 9 minutes grading a quiz, what is the probability she will spend a total of at
least 12 minutes grading the quiz?
A. 3/6
B. 3/10
C. 12/15
D. 3/15
1
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View Full DocumentQuestions 4  5 refer to the following:
The speed of cars traveling on a stretch of Interstate 5 in California is approximately normally distributed
with a mean of 72.6 miles/hour and a standard deviation of 4.78 miles/hour. The legal speed limit posted
on this stretch of Interstate 5 is 70 miles/hour.
4. Approximately what percentage of the cars travel above the speed limit?
A 3.7%
B. 2.6%
C. 70.7%
D. 72.6%
5. 60% of all cars on this stretch of Interstate 5 are going at most how fast?
A. 73.8 miles/hour
B. 71.4 miles/hour
C. 68.8 miles/hour
D. 71.2 miles/hour
Questions 6 – 8 refer to the following:
The Public Policy Institute of California estimates that 34% of workers in California have a Bachelor’s
Degree. Suppose 18 workers in California are randomly selected.
Let the random variable X = the number of workers out of one sample of 18 that have a Bachelor’s
Degree.
6. What is the distribution of X?
A. X ~ N(6.12,
2.01)
B. X ~ N(6.12,
4.04)
C. X ~ B(18, 0.34)
D. X ~ Exp(0.34)
7. In repeated surveys of 18 workers, on average how many do we expect to have a Bachelor’s Degree?
A. 7.01
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 Fall '11
 Plum
 Math, Statistics, Normal Distribution, Standard Deviation, Probability theory, Scantron

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