Question

The mean of 10 observations is 16.3 , by an error one observation is registered as 32 instead of 23.Find the correct mean.

Answer 1

Sum of observations= 10(16.3) = 163 Sum of observations - 9 = 154. Corrected mean=15.4

Answer 2

Sum of the 10 observations = 16.3 * 10 =  163.
But let us remove the wrong data observation, then sum of 9 correct observations is =  163 - 32 = 131.

Now add the correct value of the 10th observation = 131 + 23 = 154

Now find the mean = 154 /10 = 15.4