×
Log in to StudySoup
Get Full Access to Statistics - Textbook Survival Guide
Join StudySoup for FREE
Get Full Access to Statistics - Textbook Survival Guide

Using the same SAT questions described in Exercise, find

Elementary Statistics | 12th Edition | ISBN: 9780321836960 | Authors: Mario F. Triola ISBN: 9780321836960 18

Solution for problem 3CQQ Chapter 5.5

Elementary Statistics | 12th Edition

  • Textbook Solutions
  • 2901 Step-by-step solutions solved by professors and subject experts
  • Get 24/7 help from StudySoup virtual teaching assistants
Elementary Statistics | 12th Edition | ISBN: 9780321836960 | Authors: Mario F. Triola

Elementary Statistics | 12th Edition

4 5 0 294 Reviews
21
3
Problem 3CQQ

Using the same SAT questions described in Exercise, find the standard deviation for the numbers of correct answers for those who make random guesses for all 100 questions.

Exercise

There are 100 questions from an SAT test, and they are all multiple choice with possible answers of a, b, c, d, e. For each question, only one answer is correct. Find the mean number of correct answers for those who make random guesses for all 100 questions.

Step-by-Step Solution:
Step 1 of 3

Problem 3CQQ

Answer:

Step1 of 2:

We have There are 100 questions from an SAT test, and they are all multiple choice with possible answers of a, b, c, d, e. For each question, only one answer is correct. We need to find the mean number of correct answers for those who make random guesses for all 100 questions.

Here,

n =  100

S = {a,b,c,d,e}

Probability of getting correct answer P(correct) =  ⅕

Hence p = ⅕

Step2 of 2:

The mean number of correct answers for those who make random guesses for all 100 questions is given by

E(x) = np

        = 1000.20

        = 20

Therefore,E(x) = 20

 var(x) = npq

            = 1000.20

Step 2 of 3

Chapter 5.5, Problem 3CQQ is Solved
Step 3 of 3

Textbook: Elementary Statistics
Edition: 12
Author: Mario F. Triola
ISBN: 9780321836960

Unlock Textbook Solution

Enter your email below to unlock your verified solution to:

Using the same SAT questions described in Exercise, find

×
Log in to StudySoup
Get Full Access to Statistics - Textbook Survival Guide
Join StudySoup for FREE
Get Full Access to Statistics - Textbook Survival Guide
×
Reset your password