Homework Help: Statistics

Posted by Daniel on Thursday, March 7, 2013 at 10:10am.

A quiz consists of 10 questions. Each question is marked either “right” or “wrong.” For each student in the class, the instructor keeps a record of the number of right answers the student got. In the class, the average number of right answers is 6.2 and the SD of the number of right answers is 1.4.

(1) Find the average number of wrong answers.

(2) Find the SD of the number of wrong answers.

Statistics - PsyDAG, Thursday, March 7, 2013 at 11:01am
1. 10 - 6.2 = ?

2. 1.4
Statistics - Anonymous, Monday, March 11, 2013 at 5:49pm
1.3.8
2.1.4
Statistics - Gary, Tuesday, March 12, 2013 at 1:23am
"number wrong" = 10 - "number right" is a linear transformation that says, "Multiply the list by -1, then add 10." The addition does nothing to the SD, and the multiplication by -1 multiplies the SD by |-1|=1. So there's no change to the SD. In terms of the histogram, the histogram for "number wrong" is a flip of the histogram for "number right," so the SD stays the same.

Answer this Question

Related Questions

Finite Math - A biology quiz consists of 10 multiple -choice questions. 7 must ...
Probability/Statistics - A quiz consists of 10 multiple-choice questions, each ...
Math 150 - an online quiz is made of 10 multiple choice questions. each question...
statistics - 10. A student is taking a multiple choice test where each question ...
Statistics - Please help. Find the probability of getting 2 hearts if the cards ...
Statistics - A student studies for a statistics exam where all questions are ...
statistics - a test consists of true/false questions .to pass the test a student...
statistics - The following are all quiz scores of a student in a statistics ...
Binomial Distribution - A biology quiz consists of twelve multiple-choice ...
statistics - A student is taking a multiple choice test where each question have...

For Further Reading

First Name:
School Subject:
Answer: