Casio nCr Calculator (Online)
Use this tool like the nCr function on a Casio calculator. Enter whole numbers for n and r, then click calculate.
What is nCr?
The expression nCr (also written as C(n, r)) means “the number of ways to choose r items from n items when order does not matter.” This is called a combination.
Formula:
nCr = n! / (r! × (n − r)!)
Example: If you have 10 students and want to choose 3 for a team, the number of possible teams is: 10C3 = 120.
How to do nCr on a Casio calculator
If you searched for “ncr calculator casio,” you probably want both the button method and a quick online fallback. Here are the typical steps used on most Casio scientific calculators (fx-991ES, fx-991EX ClassWiz, and similar models):
Casio key sequence (general)
- Enter n (for example, 10)
- Press the nCr function (usually via SHIFT + PRB, then select nCr)
- Enter r (for example, 3)
- Press =
Why use this online Casio-style nCr calculator?
- No button hunting on different calculator models
- Works on mobile and desktop
- Handles large values with precise integer math
- Useful for homework checks and probability problems
Common use cases for nCr
1) Probability and statistics
Combinations appear in binomial probability, card problems, lottery odds, and sampling without replacement.
2) Classroom math and exams
Many high school and college questions ask for “number of ways to select” a group. That phrasing is usually a clue for nCr.
3) Real-life selection problems
Committee formation, choosing interview panels, selecting product bundles, or assigning teams without rank/order.
nCr vs nPr (important)
| Function | Meaning | Order matters? | Example |
|---|---|---|---|
| nCr | Combinations | No | Choosing 3 students for a group |
| nPr | Permutations | Yes | Assigning Gold/Silver/Bronze winners |
Worked examples
Example A: 8C2
8C2 = 8! / (2! × 6!) = 28
Example B: 15C5
15C5 = 3003
Example C: 52C5 (poker hands)
52C5 = 2,598,960 possible 5-card hands.
Input rules for this calculator
- n and r must be whole numbers (0 or greater).
- r must be less than or equal to n.
- If r = 0 or r = n, result is always 1.
Quick FAQ
Can I use decimals in nCr?
No. Standard combination calculations use non-negative integers.
Why is my Casio showing an error?
Usually because r > n, a syntax issue, or using a mode/function that doesn’t support the operation. Re-enter with whole-number values and check that you selected nCr correctly.
Does this match Casio nCr output?
Yes—this calculator follows the same combinatorial definition used by Casio calculators, with exact integer results.
Final thoughts
If you need a reliable ncr calculator casio alternative, this page gives you a fast, accurate result while also helping you understand what nCr means. Use it to verify homework, solve probability questions, and build confidence before exams.