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Evaluate n+1Cn-2 If n =15...

Evaluate n+1Cn-2 If n =15

A.

3630

B.

3360

C.

1120

D.

560

Correct answer is D

n+1(n2)(n+1)!

(n+1)+(n2)!(n2)!(n+1)!

(n+1)(n+11)(n+12)(n+13)!3!(n2)!

(n+1)(n)(n1)(n2)!3!(n2)!

(n+1)(n)(n1)3!

Since n = 15

(15+1)(15)(151)3!

16×15×143×2×1

= 560