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Susan Athena
Susan Athena, Professional w/Adv. Degree
Category: Homework
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Experience:  10+ yrs teaching & tutoring. AP essay grader. 2 masters degrees. English, IT, business.
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The number of students taking the Scholastic Aptitude Test

Resolved Question:

The number of students taking the Scholastic Aptitude Test (SAT) has risen to an all-time high of more than 1.5 million (College Board, August 26, 2008). Students are allowed to repeat the test in hopes of improving the score that is sent to college and university admission offices. The number of times the SAT was taken and the number of students are as follows.


a. Let x be a random variable indicating the number of times a student takes the SAT. Show the probability distribution for this random variable (to 4 decimals).

x = 1
x = 2
x = 3
x = 4
x = 5

b. What is the probability that a student takes the SAT more than one time (to 4 decimals)?

c. What is the probability that a student takes the SAT three or more times (to 4 decimals)?

d. What is the expected value of the number of times the SAT is taken (to 4 decimals)?

What is your interpretation of the expected value?
The input in the box below will not be graded, but may be reviewed and considered by your instructor.

e. What is the Variance and Standard deviation for the number of times the SAT is taken (to 4 decimals)?

What is the Variance?

What is the Standard deviation?
Submitted: 1 year ago.
Category: Homework
Expert:  Martin replied 1 year ago.
Hi there,

I can help you with this, but it seems there is some data missing. Can you perhaps scan and upload the original document?

Thanks
Customer: replied 1 year ago.

I think this is what is missing:


 


Number of Number of


Times Students


1 721,769


2 601,325


3 166,736


4 22,299


5 6,730

Customer: replied 1 year ago.
Relist: Answer came too late.
Expert:  Martin replied 1 year ago.
Sorry, I didn't realize there was a 15 minute deadline. I'll opt out...
Customer: replied 1 year ago.

Not a problem It just told me you were working on another problem.

Expert:  Susan Athena replied 1 year ago.
Hi. Thanks for your question.

Do you still require an answer? If you have an immediate deadline, please say so in your question.

Thank you!
Susan
Customer: replied 1 year ago.

with in the next hour would be great!

Expert:  Susan Athena replied 1 year ago.
Sure, just hold on a minute while I put it together for you!
Customer: replied 1 year ago.

Awesome! Thank you!

Expert:  Susan Athena replied 1 year ago.
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Susan Athena, Professional w/Adv. Degree
Category: Homework
Satisfied Customers: 4324
Experience: 10+ yrs teaching & tutoring. AP essay grader. 2 masters degrees. English, IT, business.
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