Question

Mean of 10 items was found to be 15. On verification, it was found that an item 21 was miscopied as 12. The correct mean is

• A. 15.9
• B. 14.1
• C. 24
• D. none of these

Answer 1

Answer: (A)

15.9

Answer 2

Observed sum of the items $= 10 \times 15 = 150$ Corrected sum of the items $= 150 - 12 + 21 = 159$ $\therefore$ Corrected mean $= \frac{159}{10} = 15.9$