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Intro to Counting and Probability
Intro to Permutations and Combinations
Combination Notation

Practice problem

Combination Notation

By BBen Ferrara

+1 contributors

Contributors

Ben Ferrara
Ruiran Xun

What is $_9C_4$ ?

Choose one answer

Option A: A

$36$

Option B: B

$9$

Option C: C

$126$

Option D: D

$16$

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