• Sep 11th 2006, 09:05 PM
baby_pinoy56
1.Find the mean and the standard deviation of this set of data.
24, 25, 15, 19, 17
2. Make up a set of five data items that has the same mean as the data set in question 1 but has a smaller standard deviation
3. Make up a set of five data items that has the same mean as the data set in Question 1 but has a larger standard deviation
4.Make up a set of data items that has the same standard deviation as the data set in question 1 but has a different mean.

Thank you SOO MUCH!:D
• Sep 12th 2006, 05:14 AM
CaptainBlack
Quote:

Originally Posted by baby_pinoy56
1.Find the mean and the standard deviation of this set of data.
24, 25, 15, 19, 17

mean=(24 +25 +15 +19 +17)/5
SD=sqrt{[(24-mean)^2 +(25-mean)^2 +(15-mean)^2 +(19-mean)^2 +(17-mean)^2]/N}

where N=5 or 4 depending how your teacher has chosen to define it.

Quote:

2. Make up a set of five data items that has the same mean as the data set in question 1 but has a smaller standard deviation
let m=mean of data set in Q1. Let the new data set be:

m, m, m, m, m.

You should calculate the mean and standard deviation of this data set
yourself.

Quote:

3. Make up a set of five data items that has the same mean as the data set in Question 1 but has a larger standard deviation
m+1000, m+1000, m-1000, m-1000, m.

You should calculate the mean and standard deviation of this data set
yourself.

Quote:

4.Make up a set of data items that has the same standard deviation as the data set in question 1 but has a different mean.
24+m, 25+m, 15+m, 19+m, 17+m.

You should calculate the mean and standard deviation of this data set
yourself.

RonL