Tutoring math, you see all kinds of scientific calculators. The tutor continues to praise the Casio fx-991ES PLUS C.

If you were to be marooned on an island with a single calculator…which one would you prefer? The question is absurd, of course. Yet, I believe I know my answer: the Casio fx-991ES PLUS C. It has seemingly endless functionality for a little scientific calculator.

Today I noticed that it calculates binomial pdf.

Example: Using the Casio fx-991ES PLUS C, find the probability of 20 successes in 35 trials when p=0.44.

Solution:

1. Press MODE, then arrow down
2. Select 3
3. Select 4
4. For a single query, select 2
5. It will ask for x (the number of successes). Key in 20 =
6. Next, it will ask for N (the number of trials). Key in 35 =
7. Now it will ask for p (the probability of success each time). Key in .44 =
8. Hopefully you receive the answer 0.0401

HTH:)

Source:

Casio fx-991ES PLUS C User’s Guide

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.