The mean of 50 observations was 30. It was found later that an observation 48 was wrongly taken as 23. The corrected new mean is	Choose the correct choice from the following options.
A) 35.2
B) 36.1
C) 30.5
D) 39.1
E) none

Rationale: "sol . therefore correct sum = ( 30 × 50 + 48 – 23 ) = 1525 . therefore correct mean = 1525 / 50 = 30.5 . answer c"
Answer: C