Francine makes several measurements of the mass of a metal block. The data set is shown in the table below:

\begin{tabular}{|c|c|}
\hline
Measurement & Mass of metal block [tex]$( g )$[/tex] \\
\hline
1 & 20.73 \\
\hline
2 & 20.76 \\
\hline
3 & 20.68 \\
\hline
4 & 20.75 \\
\hline
\end{tabular}

After analyzing this data set, Francine calculates a value of [tex]$20.73 g$[/tex]. Which of these characteristics has been calculated?

A. mean
B. median
C. mode
D. range



Answer :

Let's analyze Francine's data set to determine which characteristic of the measurements matches the value of \(20.73 \, \text{g}\).

The measurements are:
- 20.73
- 20.76
- 20.68
- 20.75

### 1. Mean

The mean (or average) is calculated by summing all the values and then dividing by the number of observations.

[tex]\[ \text{Mean} = \frac{\text{Sum of all measurements}}{\text{Number of measurements}} \][/tex]

Calculating the sum:
[tex]\[ 20.73 + 20.76 + 20.68 + 20.75 = 82.92 \][/tex]

There are 4 measurements. So,
[tex]\[ \text{Mean} = \frac{82.92}{4} = 20.73 \][/tex]

### 2. Median

The median is the middle value of a data set that has been arranged in ascending order. If there is an even number of observations, the median is the average of the two middle numbers.

Arranging the numbers in ascending order:
[tex]\[ 20.68, 20.73, 20.75, 20.76 \][/tex]

Since there is an even number of observations, the median is:
[tex]\[ \text{Median} = \frac{20.73 + 20.75}{2} = \frac{41.48}{2} = 20.74 \][/tex]

### 3. Mode

The mode is the value that appears most frequently in a data set.

In this data set, each measurement occurs exactly once. So, there is no mode for this data set.

### 4. Range

The range is the difference between the maximum and minimum values in the data set.

Maximum value = 20.76
Minimum value = 20.68

[tex]\[ \text{Range} = 20.76 - 20.68 = 0.08 \][/tex]

### Conclusion

Since Francine calculated a value of [tex]\(20.73 \, \text{g}\)[/tex], and this matches the mean calculated above, Francine has calculated the mean of the data set.