Q12 of 140 Page 267

Evaluate , when n = 15 and r = 12.

Given : n = 15 and r = 12


To Find : Value of at given n and r


Formula :


•


•


Let ,



Substituting n = 15 and r = 12 in above equation,




By using above formula,



Cancelling (12!) from numerator & denominator,



∴x = 455


Conclusion : Value of at n = 15 and r = 12 is 6.


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