Multiple choice

The mean of 10 observations is 16.3. If one observation is registered as 32 instead of 23, then new mean is

  1. 14.8

  2. 15.4

  3. 16.1

  4. 16.6

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Original sum = 10 * 16.3 = 163. The error is 32 - 23 = 9. Correct sum = 163 - 9 = 154. New mean = 154 / 10 = 15.4.

AI explanation

To correct the incorrect observation, subtract the wrong value and add the correct value to the total sum: (10 * 16.3) - 32 + 23 = 154. The new mean is the corrected sum divided by the total number of observations: 154 / 10. This calculation gives a new mean of 15.4.