# Ti-89 Calculator question (Statistics)

1. Mar 14, 2015

### AKJ1

1. The problem statement, all variables and given/known data

Calculate the mean and standard deviation for the random variable X which equals the sum of the dots facing upward when two standard six-sided dice are rolled.

3. The attempt at a solution

In List 1, I entered all the possible values of the random variable X:
2,3,4,5,6,7,8,9,10,11,12

the probability distribution formula I was given is

Px = (6-abs(7-X))/36

So then for List 2 I entered (6-abs(7-List1))/36

Thus now in List 2 I have the probability for each of the possible random variable values.

Up to this point I have exactly what my professor has.

Next my professor (using a Ti84) goes back to the home screen and enters "1-Var Stats L1,L2" for List 1 and 2 respectively and then obtains the necessary values.

I am using a Ti-89, so upon entering my values I went to F-4 --> 1-Var Stats---> and under "List:" I entered L1,L2 (the names of my list) and it gave me a syntax error.

Thank you for any input.

2. Mar 14, 2015

### Staff: Mentor

Which syntax error?

3. Mar 17, 2015

### Ray Vickson

I do not own a Ti-89, but I looked on-line for information about "Ti-89 + statistics", and found
http://facstaff.cbu.edu/~wschrein/media/Stat/TI89man.pdf ,
which has information about entering lists. Pages 4-5 give some examples of use.