Little programs for the 'TI-nspire CX' calculator. Written in Lua. You may not be able to execute the .lua files, because they are using some TI-nspire libraries/functions.
After putting in the known values into the fourfould table or tree diagram, press 'tab' to let the script show the calculable values. Press 'esc' to delete all values.
On the fourfold table you can also press the arrowkey down to convert all values into absolute frequencies, but you have to put in the total value into the red field instead of '100'. If you want to convert the absolute frequencies into percent values, you can press the arrowkey up.
On the tree diagram, you have the possibility to round the values to chosen decimal places, by pressing the arrowkey down. Notice that you should not continue calculating with rounded values. This could cause calculating errors in the script.