To find the median on a TI-84, enter your data into a list, then run the 1-Var Stats command from the STAT menu. The median appears on the second screen of results after you scroll down. There’s also a quicker method using the median function directly. Here’s how both approaches work, step by step.
Enter Your Data Into a List
Before you can calculate anything, your numbers need to be stored in one of the calculator’s lists. Press STAT, then select 1:Edit. This opens the list editor, where you’ll see columns labeled L1, L2, and so on.
Move your cursor to the first empty row under L1 and type each data value, pressing ENTER after each one. If L1 already has old data in it, highlight the L1 header at the top of the column, press CLEAR, then ENTER to wipe it before you start. Your numbers don’t need to be in any particular order for the median calculation to work.
Find the Median With 1-Var Stats
This is the most common method because it gives you the median along with the mean, standard deviation, and other summary statistics all at once.
- Press STAT, then use the right arrow to scroll over to the CALC tab.
- Select 1:1-Var Stats and press ENTER.
- On newer TI-84 models (the CE and Plus CE), a setup screen appears. Make sure the List field says L1 (or whichever list holds your data), leave FreqList blank unless you’re using frequency data, then arrow down to Calculate and press ENTER.
The first screen of results shows the mean (x̄), the sum of x values, the standard deviation, and the count (n). The median is not on this first screen. Press the down arrow several times to scroll to the second screen, where you’ll see a five-number summary: the minimum (minX), the first quartile (Q1), the median (Med), the third quartile (Q3), and the maximum (maxX). The value next to “Med” is your answer.
On older TI-84 models (without the setup screen), pressing ENTER after selecting 1-Var Stats runs the calculation immediately on L1 by default. If your data is in a different list, type the list name (for example, press 2nd then 2 for L2) before pressing ENTER.
Use the Median Function Directly
If you only need the median and don’t care about the rest of the statistics, you can skip 1-Var Stats entirely and use the built-in median function.
- Press 2nd then STAT to open the LIST menu.
- Arrow over to the MATH tab.
- Select 4:median(.
This pastes “median(” onto your home screen. Now type the list name. For L1, press 2nd then 1. Close the parenthesis and press ENTER. The calculator returns the median immediately.
You can also type values directly into the function without storing them in a list first. Type median({5,8,12,3,7}) using curly braces (found above the parentheses keys with 2nd) and press ENTER. This is handy for quick, one-off calculations when you don’t need to save the data.
Working With Frequency Lists
Sometimes your data comes as a table of values and their frequencies, like “the value 10 appears 3 times, 15 appears 5 times,” and so on. Instead of entering 10 three separate times, put the values in L1 and the frequencies in L2. When running 1-Var Stats, set the FreqList field to L2 (or type L1, L2 after the command on older models). The calculator accounts for the repeated values when computing the median.
The direct median function works the same way. Type median(L1, L2) where L2 is your frequency list.
If You Get an Error
Two errors come up most often. An ERR:INVALID DIM usually means a Stat Plot is turned on but pointing to an empty list. Press 2nd then Y= to open Stat Plots and turn off any plots you aren’t using, or press 4:PlotsOff from that menu to turn them all off at once.
An ERR:DIM MISMATCH means your two lists have different numbers of entries. This happens when you’re using a frequency list and L1 has, say, six values but L2 only has five frequencies. Go back into the list editor (STAT, 1:Edit) and check that both lists have the same number of rows.