n/2+n/2+1 n/2+1 is it the formula that we use for even&odd

No, those are not the correct formulas for finding the median for even and odd numbers of data points.

Here are the correct ways to find the position of the median:

• For an odd number of data points ($n$): The median is the value at the position given by: $\frac{n+1}{2}$

• For an even number of data points ($n$): The median is the average of the values at two positions: $\frac{n}{2} \quad \text{and} \quad \frac{n}{2} + 1$ So, you find the values at these two positions and then calculate their average.