MATHEMATICS
JAMB 2012 - Question 47
Mathematics 2012 JAMB Past Questions - Question 47: Evaluate n+1Cn-2 If n =15
A:
B:
C:
D:
Correct Answer
D
Explanation
n+1(n−2)/(n+1)!(n+1)+(n−2)!(n−2)!/(n+1)!(n+1)(n+1−1)(n+1−2)(n+1−3)!/3!(n−2)!(n+1)(n)(n−1)(n−2)!/3!(n−2)!(n+1)(n)(n−1)/3!Since n = 15(15+1)(15)(15−1)/3!16×15×143×2×1= 560

