the average of 11 results is 42 , if the average of first 5 results is 49 and that of the last 7 is 52 . find the fifth result ? Choose the correct choice from the following
A) 145  B) 146  C) 147  D) 148  E) 149

Rationale: 1 to 11 = 11 * 42 = 462 1 to 5 = 5 * 49 = 245 5 to 11 = 7 * 52 = 364 5 th = 245 + 364 – 462 = 147 answer : c
Answer: C