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Big Ideas Math Geometry, 2014

BI

Big Ideas Math Geometry, 2014 View details

5. Permutations and Combinations

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Exercise 27 Page 704

Recall the formula for a combination, _n C_r = n!/(n-r)! r!.

1

Practice makes perfect

To evaluate the given combination, we will use the corresponding formula. _n C_r = n!/(n-r)! r! We are given that n=9 and r=9. Let's substitute these values into the formula.

_n C_r = n!/(n-r)! r!

n= 9, r= 9

_9 C_9 = 9!/( 9- 9)! 9!

Subtract term

_9 C_9 = 9!/0! 9!

a/b=.a /9!./.b /9!.

_9 C_9 = 1/0!

0!=1

_9 C_9 = 1/1

a/1=a

_9 C_9 = 1

Subchapter links

Communicate Your Answer p.699

Monitoring Progress p.700-703

Exercises p.704-706