College

Last week's and this week's daily high temperatures are shown in the table below.

[tex]
\[
\begin{tabular}{|c|c|c|c|c|c|c|c|}
\hline
\multicolumn{8}{|c|}{\textbf{High Temperatures for This Week and Last Week}} \\
\hline
\begin{tabular}{c}
\textbf{High Temperatures} \\
\textbf{This Week ( ${ }^{\circ} F$ )}
\end{tabular} & 65 & 73 & 73 & 74 & 73 & 75 & 71 \\
\hline
\begin{tabular}{c}
\textbf{High Temperatures} \\
\textbf{Last Week ( ${ }^{\circ} F$ )}
\end{tabular} & 68 & 51 & 62 & 66 & 85 & 72 & 72 \\
\hline
\end{tabular}
\]
[/tex]

How much greater is this week's median temperature than last week's median temperature?

A. 2 degrees
B. 3 degrees
C. 4 degrees
D. 5 degrees

Answer :

We are given the high temperatures for two weeks. To find the difference in the medians of the temperatures, follow these steps:

1. Write down the temperatures:

  This Week: [tex]$65,\,73,\,73,\,74,\,73,\,75,\,71$[/tex]

  Last Week: [tex]$68,\,51,\,62,\,66,\,85,\,72,\,72$[/tex]

2. Sort each set of temperatures from least to greatest.

  For This Week, the sorted list is:
  [tex]$$65,\,71,\,73,\,73,\,73,\,74,\,75$$[/tex]

  For Last Week, the sorted list is:
  [tex]$$51,\,62,\,66,\,68,\,72,\,72,\,85$$[/tex]

3. Since there are [tex]$7$[/tex] values in each list (an odd number), the median is the middle number, which is the [tex]$4^\text{th}$[/tex] number in the sorted list.

  For This Week, the median is the [tex]$4^\text{th}$[/tex] value:
  [tex]$$\text{Median}_{\text{this week}} = 73$$[/tex]

  For Last Week, the median is also the [tex]$4^\text{th}$[/tex] value:
  [tex]$$\text{Median}_{\text{last week}} = 68$$[/tex]

4. Find how much greater this week's median is than last week's median by subtracting:
  [tex]$$73 - 68 = 5$$[/tex]

Thus, this week's median high temperature is [tex]$\boxed{5}$[/tex] degrees greater than last week's.