I'll give you a question, please answer with step-by-step reasoning process.
The average of seven results is 156 and that of the first six is 169. The fifth result is?\nOptions:\n(A) 120\n(B) 160\n(C) 89\n(D) 78\n(E) 148

(D)
7 * 156 â€“ 6 * 169 = 78.

The final answer: (D)