Question

The Mean of $10$ observation is $15$, due to an error one observation is registered as $23$ instead of $32$ then find the correct mean.

Answer 1

Mean:It can be define as the Ratio of the Sum of Number of Observations to the Number of Observations.

Mean of $10$ observations$=$Sum of number of observations/Number of observations.

$15=\frac{Sumofnumberofobservations}{10}$

$\therefore$Sum of $10$ of observations$=150$

By mistake,a wrong number is registered.

So, removing the wrong observation$=150-23=127$

now, adding the correct observation$127+32=159$

So, mean of $10$ observations$=\frac{159}{10}=15.9$

Hence mean of $10$ onservations is $15.9$