How do you find the median of a list of temperatures?

1 answer

To find the median of a list of temperatures (or any set of numbers), follow these steps:

  1. Organize the Data: Arrange the list of temperatures in ascending order from the smallest to the largest.

  2. Count the Numbers: Determine the total number of temperatures in the list.

  3. Find the Median:

    • If the total number of temperatures (n) is odd, the median is the middle number. You can find the index of the median using the formula: \[ \text{Median index} = \frac{n}{2} \] (using zero-based indexing).
    • If n is even, the median is the average of the two middle numbers. You find the indices as follows: \[ \text{Median indices} = \frac{n}{2} - 1 \quad \text{and} \quad \frac{n}{2} \]
  4. Calculate the Median:

    • For an odd n, the temperature at the median index is the median.
    • For an even n, the median is the average of the temperatures at the two middle indices.

Example

Consider the following list of temperatures: 72, 75, 68, 70, 74.

  1. Organize the Data: 68, 70, 72, 74, 75
  2. Count the Numbers: There are 5 temperatures (n=5).
  3. Find the Median: Since 5 is odd, the median is the middle value, which is at index 2:
    • Median = 72 (the third number in the ordered list).

If the list were: 72, 75, 68, 70, 74, 73:

  1. Organize the Data: 68, 70, 72, 73, 74, 75
  2. Count the Numbers: There are 6 temperatures (n=6).
  3. Find the Median: Since 6 is even, find the average of the two middle values (at indices 2 and 3):
    • Median = (72 + 73) / 2 = 72.5.

This is how you calculate the median temperature from a list.