probabilityv

A school's administrators are concerned about absenteeism at their school
and the e ect it has on students' grades. The following data were compiled, based on a sample of students.
Student's Absent Medium Absent
Grade Infrequently Absent Frequently
Low 1 9 8
Medium 6 35 7
High 8 9 2
a. What is the probability that a randomly selected student will have a low grade?

This would be 1/15 + 9/53 + 8/17 right?

b. What is the probability that a randomly selected student absent frequently?

8/18 + 7/48 + 2/19

c. Are grades and frequency in absent independent events? Why?

Not sure but i think they are dependent

d. Knowing that a randomly selected student has high grade, what is the probability that student is absent frequently?
2/19
e. What is the probability that a randomly selected student has either high grade or absent frequently?
I don't know how to calculate this

asked by lisa
  1. a. total of low grade students/grand total of students = 18/85

    b. total of frequently absent students/grand total of students

    c. Yes,try a Chi-squared (X^2) test to show why

    d. Yes!

    e. Either-or probabilities are found by adding the probabilities of the individual events. Total number of high grade/grand total + total number of absent frequently/grand total

    posted by PsyDAG

Respond to this Question

First Name

Your Response

Similar Questions

  1. juvenile cime

    what are roles of school administrators and teachers concerning school-based crime issues
  2. English

    1. My school begins at 8:30 a.m. like Bora's school. 2. Our school begins at 8:30 a.m. like Bors'a school. (Which one is correct? Are both OK, my school and our school?) 3. My school and Bora's school are the same as follows.
  3. speech

    You are concerned about the high rate of school droupouts in your community and have recentky addressed the youth at a local secondary school who were thinking of dropping out of school and look for job.please help me its urgent
  4. English

    posted by rfvv yesterday at 7:25am. The dietitian says, "This is the school cafeteria." What does the school cafeterian mean? 1. This is the (only) school cafeterian of our school. 2. This is the specific school cafeterian of our
  5. English

    1. At school, I enjoy chatting with my close friends. 2. At school, I enjoy cleaning with other classmates. 3. At school, I enjoy playing soccer in the playground. 4. At school, I enjoy eating cookies at the school shop. 5. At
  6. English

    The dietitian says, "This is the school cafeteria." What does the school cafeterian mean? 1. This is the (only) school cafeterian of our school. 2. This is the specific school cafeterian of our school. [What does "This is the
  7. Introductin to Psychology

    Alyssa's family had moved in the middle of her junior year in high school. At her old school she was a varsity cheer leader, vice president of the student council, and would ave been presented as the school "sweetheart" at
  8. Management (open to everyone)

    My ideas are after the question. Please add to them or comment. Assume that you represent the top administrators of a large university with 15,000 students. Over the past three years there have been an increasing number of
  9. English

    posted by rfvv Friday, April 27, 2018 at 10:38pm 1. He hurries to school. 2. He goes to school in a hurry. [Are both the same? What is the difference between #1 and #3, and between #2 and #4?0 3. He hurries to the school. 4. He
  10. macroeconomics

    The No Child Left Behind law rewards schools and teachers based on students’ performance on standardized tests. Some school systems have instituted bonus programs for teachers whose students perform above average. Discuss this

More Similar Questions