CAT Exam Model Paper 2 with solutions for free online practice

f(9, 2, k, 0, 9, 4)
= f(9, 4) + f(2, k, 0, 9)+ (9 + 2 + k + 0 + 9 + 4)
= f(4, 0) + f(0, 9)+ [f(2, 9) + f(k, 0)+ (2 + k + 0 + 9)]+ 24 + k
= 11 + 4 + [{f(9, 0) + f(0,2)} + f(k, 0) + (11 + k)]+ 24+ k
= 15 + [48 + f(k, 0) + (11 + k)] + 24 + k
= 98 + 2k + f(k, 0)
= 98 + 2 k + [

k(k+1)

2

+1]=124
⇒ k‌2 +5k -50 = 0
⇒ k = − 10 or k = 5
Since k is a positive integer, hence k = 5.