1. The problem is to find the median, lower quartile (Q1), and upper quartile (Q3) of a data set. 2. The median is the middle value when the data is ordered. If the number of data points $n$ is odd, median is the value at position $\frac{n+1}{2}$. If $n$ is even, median is the average of values at positions $\frac{n}{2}$ and $\frac{n}{2}+1$. 3. The lower quartile (Q1) is the median of the lower half of the data (below the median). 4. The upper quartile (Q3) is the median of the upper half of the data (above the median). 5. To find these, first order the data from smallest to largest. 6. Then find the median as described. 7. Split the data into lower and upper halves (excluding the median if $n$ is odd). 8. Find the median of the lower half to get Q1. 9. Find the median of the upper half to get Q3. This method divides the data into four equal parts, helping understand the distribution.