The mean of 50 observations was 40. It was found later that an observation 48 was wrongly taken as 23. The corrected new mean is  Choose the correct answer:
A) 40.46
B) 36.1
C) 36.5
D) 39.1
E) none

Rationale: "sol . therefore correct sum = ( 40 × 50 + 48 – 23 ) = 2023 . therefore correct mean = 2023 / 50 = 40.46 . answer a"
Answer: A