When to use the formula (nCr x nCr)/nCr?

Click For Summary
SUMMARY

The formula (nCr x nCr)/nCr simplifies to nCr, indicating that it is used to calculate combinations of a set. In the discussion, the example provided was 5C2 x 4C3, which illustrates the application of this formula in combinatorial problems. Understanding the context of the variables represented by n, r, and their respective combinations is crucial for proper application. This formula is particularly relevant in probability and statistics when determining the number of ways to choose items from a larger set.

PREREQUISITES
  • Understanding of combinatorial mathematics
  • Familiarity with the concept of combinations (nCr)
  • Basic knowledge of probability theory
  • Ability to manipulate algebraic expressions
NEXT STEPS
  • Study the properties of combinations and permutations
  • Learn how to derive the formula for nCr
  • Explore applications of combinations in probability problems
  • Investigate advanced combinatorial identities and their proofs
USEFUL FOR

Students studying combinatorial mathematics, educators teaching probability, and anyone interested in applying mathematical concepts to real-world problems.

jasper10
Messages
55
Reaction score
0

Homework Statement



I was wondering for what situations one uses the formula:
(nCr x nCr)/ nCr ?
Thanks

Homework Equations



nCr
 
Physics news on Phys.org
jasper10 said:
I was wondering for what situations one uses the formula:
(nCr x nCr)/ nCr ?
You mean (nCr x nCr)/ nCr = nCr? ;)

There's a reason you use different letters to represent different quantities. It's hard to answer your question when you have removed all that information from the formula.
 
well i mean for example,

5C2 x 4C3 / nCr
 

Similar threads

Counting problem -- Lining up colored marbles....
  • · Replies 7 ·
Replies
7
Views
2K
Counting problems: dancing couples & books and children
  • · Replies 7 ·
Replies
7
Views
2K
How Many Committees Can Be Formed from Five Student Representatives?
  • · Replies 4 ·
Replies
4
Views
3K
Algebraically Determining the Solution to this Combination
  • · Replies 7 ·
Replies
7
Views
2K
MHB In how many ways can Ben paint his apartment?
  • · Replies 4 ·
Replies
4
Views
1K
Find the number of triangles given n lines
  • · Replies 9 ·
Replies
9
Views
9K
Probability that bulb is defective questions
  • · Replies 6 ·
Replies
6
Views
4K
Finding Permutations with Repetitions: n, x, a, b, c, d
  • · Replies 12 ·
Replies
12
Views
3K
Permutation and Combination Problem
  • · Replies 4 ·
Replies
4
Views
2K
Statistical Combinations/Permutations
  • · Replies 4 ·
Replies
4
Views
2K