A man whose bowling average is 12.4, takes 5 wickets for 26 runs and there by decreases his average by 0.4. the number of wickets taken by him before his last match is?	Choose the correct option.
A) 82
B) 83
C) 84
D) 85
E) 86

Rationale: "12.4 x + 26 / ( 5 + x ) = 12 12.4 x + 26 = 60 + 12 x x = 34 / 0.4 = 85 answer : d"
Answer: D