JAMB Economics 2024 Paper

Concept:The formula $\frac{N + 1}{2}$ locates the position of the median in an ordered data set.Explanation:The median is the middle value when numbers are arranged in order. Here, $N$ represents the total number of values in the data set. To find the median, arrange all values from lowest to highest first. Then, calculate the position of the middle value using $\frac{N + 1}{2}$. The result tells you which value in the ordered list is the median. For example, if $N = 9$, then $\frac{9 + 1}{2} = 5$. So the 5th value in the ordered data is the median. If $N$ is odd, this formula gives a whole number position. If $N$ is even, the median is the average of the two middle values, often found using the positions $\frac{N}{2}$ and $\frac{N}{2} + 1$. Thus, $\frac{N + 1}{2}$ is not used to find the mean, mode, or standard deviation; it is specifically connected to the median.Answer:A. median