# Statistics : Tchebycheff

1. Jan 17, 2016

### masterchiefo

• Member warned about posting with no effort
1. The problem statement, all variables and given/known data
Hello all,

I have a one number stat:

Xi
2
4
5
6
6
8
10

Tchebycheff :
It ask me to find the value of K.

Interval of confidence: 89%

I know 1-1/k2
I have no idea how to calculate the value of K.
Do I have to somehow use the interval of confidence?

I checked my book and notes and there is nothing stating how to calculate K.
I just need to know the formula. Thanks.

2. Jan 17, 2016

### Ray Vickson

(1) Your question makes no sense. 89% confidence interval for what? What do you mean by K?
(2) You are required to show your work before getting any help.

3. Jan 17, 2016

### masterchiefo

This is all I have, no other info from teacher.
trust me I would love to show any work...but...I have no idea what is K. or what is the relation with 89% confidence interval. it probably have no relation and its just there to mess with my head.

All I have is this on my paper:
Fill the blank:

Xi
2
4
5
6
6
8
10

Tchebycheff :
Interval of confidence: 89%
K=

4. Jan 17, 2016

### HallsofIvy

Staff Emeritus
You titled this "Tychebycheff". Are you saying you do not know what Tchebycheff's theorem is? If so did you try looking it up?

Tchebycheff's theorem says that if X is a random variable with mean $\mu$ and standard deviation $\sigma$ then the probability that $|x- \mu|\ge k\sigma$ is less than or equal to $1/k^2$. What are the mean and standard deviation for this data? What are the upper and lower numbers such that 89% of the data is closer to the mean than those?