Solution 34795: Calculating Two-Variable Statistics Using the TI-84 Plus C Silver Edition Graphing Calculator.
How do I calculate two-variable statistics using the TI-84 Plus C Silver Edition?
The example below will demonstrate how to calculate two-variable statistics using the TI-84 Plus C Silver Edition.
Data for this example:
• Press [STAT]  to access the STAT list edirtor.
• Enter the data in the L1 and L2 lists, making sure to press [ENTER] after each entry.
• Press [2nd] [MODE] to QUIT and return to the home screen.
Calculating the two-variable statistics:
• Press [STAT], arrow right to highlight the CALC menu and press  to select the 2-Var Stats function.
• From here, the XList should be L1, the YList should be L2 and the FreqList should be blank. You can press [2nd] and  to obtain L1, and then [2nd] and  to obtain L2 if necessary.
• Press [ENTER] on "Calculate", and the two-variable statistics data will be displayed. The [up arrow] and [down arrow] keys can be used to scroll through the data.
Please see the TI-84 Plus C Silver Edition guidebook for additional information.