The average of 10 numbers is 40.2. Later it is found that two numbers have been wrongly copied. The first is 16 greater than the actual number and the second number added is 13 instead of 31. Find the correct average.  Select:
A) 40.2 B) 40.4 C) 40.6 D) 40.8 E) none of the above

Rationale: "sum of 10 numbers = 402 corrected sum of 10 numbers = 402 – 13 + 31 – 16 = 404 hence , new average = 404 ⁄ 10 = 40.4 answer b"
Answer: B