Normal distribution and standard deviation

A professor would like to use the normal distribution to assign grades such that 5% of students receive A's.  If the exam average is 62 with a standard deviation of 13, what grade should be the cutoff for an A? 

Liked this question? Tell your friends about it

2 Answers

Order by
Oldest to Newest
Newest to Oldest
Votes

95% will be 1.645 standard deviations above the mean = 62 + 1.645 x 1.3 = 83.3 so a grade of 84 or higher should get an A.

Related Questions

Other people asked questions on similar topics, check out the answers they received:

Asked: What will be the development trend of mining ...

Withthe rapid development of science and technology, we have entered the digital information age.This is known to all that informatization has four characteristics , namely intelligent , electronic ...

Asked: How do I solve this simultaneous equation. Been a ...

-462=x-y x=-2y The question is with regards to a three bar model and the residual stress in welds. The answer is: x=-154 MPa and y is +308 MPa x is actually stress2 and y is stress1 I'm so ...

Asked: What is the mathematical term for 9 squared ...

what is the mathematical term for 9 squared multiplied by b squared equals c squared?

More Questions

Deviated Septum: Can it be pushed back into place by repeated finger

No. Symptoms may be helped by medication, but Medications are only a temporary fix, however, and won't correct a deviated septum. Surgical repair If you experience especially bothersome symptoms — such as significant airway obstruction, chronic sinusitis or frequent nosebleeds — you may ...

Are there written procedures for phasing in a power transformer in a

There has to be. Find in t he companys operation manual.

What is the normal sed rate for a 74 year old woman

In Wikipedia, the given rate for women is a formula == add 10 to your age and then divide by 2 to get the normal maximum sed rate. So at 74, a normal sed rate for a woman would be between 0 and 42. Values are increased in states of anemia, and in black populations. For the whole Wiki article, see ...

Htp://www.irs.gov/what is the amount of standard deduction

Your total income, minus your deductions, results in your taxable income. The biggest deductions for most people are the "Standard Deduction" (if you do not itemize) and the "Personal Exemptions". The Standard Deduction for a single person is $5700 (plus $1400 if over 64 or blind), for married ...