The mean of 30 values was 140. It was detected on rechecking that one value 145 was wrongly copied as 135 for the computation of the mean. Find the correct mean.  Choose the correct choice.
A) 151 B) 140.33 C) 152 D) 148 E) none of the above

Rationale: "corrected mean = 140 × 30 − 135 + 145 / 30 = 4200 − 135 + 145 / 30 = 4210 / 30 = 140.33 answer b"
Answer: B