SAMPLE MEAN OF VARIABLE X IS CALCULATION AS Select one: bar (x)=sum _(i=1)^bar (k)n_(i)x_(i) bar (x)=(1)/(n)sum _(i=1)^bar (k)x_(i) O bar (x)=(1)/(n)sum _(i=1)^nn_(i)x_(i) O bar (x)=(1)/(k)sum _(i=1)^bar (k)n_(i)x_(i) bar (x)=(1)/(n)sum _(i=1)^bar (k)n_(i)x_(i)

The correct answer is: $\bar {x}=\frac {1}{n}\sum _{i=1}^{\bar {k}}x_{i}$<br /><br />Explanation: The sample mean of a variable X is calculated by taking the sum of all the values of X and dividing it by the total number of values. In the given options, the correct formula for calculating the sample mean is $\bar {x}=\frac {1}{n}\sum _{i=1}^{\bar {k}}x_{i}$, where n is the total number of values and $\bar {k}$ represents the number of groups or categories.