# TI-89 Titanium - Probability - Expected Value

• Calculators
• rekshaw

#### rekshaw

EDIT: I found the solution, it can be done using the TwoVar() function on the TI-89 and it gives you a whole lot more than just the expected value. thanks anyways

Hello everyone! :)

I hope I will get an answer for this!

As a USER-DEFINED function I would like to be able to calculate the Expected Value of n outcomes with their respective probabilities (also in a single matrix)

it should look something like this:

$\begin{pmatrix} 1 & 1/6 \\ 2 & 1/6 \\ 3 & 1/6 \\ 4 & 1/6 \\ 5 & 1/6 \\ 6 & 1/6 \end{pmatrix}$

To find the expected value I would need to do:

$(1 \times 1/6) + (2 \times 1/6) + ... + (6 \times 1/6) = E(X)$

Basically, multiply each outcome with its probability and finally sum the whole lot...

IDEALLY...I would like to be able to make a single 2 x n matrix with outcomes and probabilities side-by-side, store it as A and be able to do:
Code:
expval(A)

or...which is faster to type: make a n*2 matrix!

Anyways...sorry for the long post, any help will be much appreciated!

Last edited by a moderator:
Nice solution!

## What is the TI-89 Titanium calculator?

The TI-89 Titanium is a graphing calculator manufactured by Texas Instruments. It is designed for high school and college level mathematics and allows for advanced mathematical functions and graphing capabilities.

## What is probability on the TI-89 Titanium?

The TI-89 Titanium has a built-in probability distribution function that allows users to calculate probabilities for various distributions, such as binomial, normal, and poisson. It also has functions for calculating expected value, standard deviation, and other important statistical measures.

## How do I use the expected value function on the TI-89 Titanium?

To calculate expected value on the TI-89 Titanium, you can use the command "EVAL(" followed by the function or expression you want to find the expected value for. For example, to find the expected value for rolling a six-sided die, you would enter "EVAL(1/6*(1+2+3+4+5+6))" into the calculator.

## Can the TI-89 Titanium perform hypothesis testing?

Yes, the TI-89 Titanium has built-in functions for performing hypothesis tests, such as t-tests and z-tests. These functions can be found in the "Stats/List Editor" menu under the "Tests" option.

## Is the TI-89 Titanium allowed on standardized tests?

The TI-89 Titanium is not allowed on some standardized tests, such as the SAT and ACT. However, it is allowed on other tests, such as the AP Calculus and AP Statistics exams. It is always best to check with the testing organization or your teacher/professor to confirm if the calculator is allowed on a specific exam.