statistics

posted by .

After years of data collection by college students, it has been determined that the distribution of course grades in Ms. Green’s Statistic II class follows a normal distribution with a mean of 62 and a standard deviation of 14.


(a) A student will pass Ms. Green’s course if he or she receives a course grade of 70 or higher. A current student in Ms Green’s class is chosen at random. What is the probability that the student will NOT receive a passing grade in Ms. Green’s class?


(b) What is the probability of a student receiving a “B” (i.e. a course grade greater than or equal to 80, but less than 90) in Ms. Green’s class?


(c) What range of course grade values would be considered outliers for Ms. Green’s class?

  • statistics -

    a. Z = (score-mean)/SD

    Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion related to that Z score.

    b. Use same equation to find proportions between the two Z scores.

    c. I would say any score > ± 3 SD.

    I'll let you do the calculations.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Math (Statistic)

    Considered the sampling distribution of a sample mean obtained by random sampling from an infinite population. This population has a distribution that is highly skewed toward the larger values. a) How is the mean of the sampling distribution …
  2. stats

    Suppose the mass of college students can be modeled by the normal distribution. We believe the mean of the normal distribution is 72 kg. We randomly sample 18 students and find an average of 69 kg and a standard deviation of 4kg. A. …
  3. college

    Suppose that, for a certain exam, a teacher grades on a curve. It is known that the grades follow a normal distribution with a mean of 70 and a standard deviation of 7. There are 45 students in the class. How many students should receive …
  4. AP Statistics - sampling distribution help

    The composite scores of students on the ACT college entrance examination in a recent year had a Normal distribution with mean µ = 20.4 and standard deviation = 5.8. 1) What is the probability that a randomly chosen student scored …
  5. AP Statistics - Sampling Distribution Help

    The composite scores of students on the ACT college entrance examination in a recent year had a Normal distribution with mean µ = 20.4 and standard deviation = 5.8. 1) What is the probability that a randomly chosen student scored …
  6. statistics

    Percentage grades in a large physics class follow a normal distribution with mean 58. It is known that 3% of students receive grades less than 39.2. What is the standard deviation of grades in the class?
  7. Statistics

    The distribution of IQ scores is a nonstandard normal distribution with a mean of 100 and a standard deviation of 15. What are the value of the mean and standard deviation after all IQ score have been standardized by converting them …
  8. statistics(business)

    Large group of students took a test in English and the final grades have a mean of 75 and a standard deviation of 8. If we can approximate the distribution of these grades by a normal distribution. What percentage of the students (ii) …
  9. statistics

    Large group of students took a test in English and the final grades have a mean of 75 and a standard deviation of 8. If we can approximate the distribution of these grades by a normal distribution. What percentage of the students (ii) …
  10. Statistics

    A college statistics class conducted a survey of how students spend their money. They asked 25 students to estimate how much money they typically spend each week on fast food. They determined that the mean amount spent on fast food …

More Similar Questions