The stem-and-leaf plot displays data collected on the size of 15 classes at two different schools.

\begin{tabular}{r|l|l}
Bay Side School & & Seaside School \\
\hline [tex]$8,6,5$[/tex] & 0 & 5,8 \\
[tex]$8,6,5,4,2,0$[/tex] & 1 & [tex]$0,1,2,5,6,8$[/tex] \\
[tex]$5,3,2,0,0$[/tex] & 2 & [tex]$5,5,7,7,8$[/tex] \\
& 3 & 0,6 \\
2 & 4 &
\end{tabular}

Key: [tex]$2|1| 0$[/tex] means 12 for Bay Side and 10 for Seaside

Part A: Calculate the measures of center. Show all work. (2 points)

Part B: Calculate the measures of variability. Show all work. (1 point)

Part C: If you are interested in a smaller class size, which school is a better choice for you? Explain your reasoning.



Answer :

Sure, let's go through this step-by-step:

### Part A: Calculate the measures of center

1. Mean
- Bay Side School: To find the mean, you sum all the class sizes and divide by the number of classes.
- Bay Side School class sizes: 8, 6, 5, 18, 16, 15, 14, 12, 10, 25, 23, 22, 20, 20, 42
- Sum of Bay Side School class sizes: [tex]\( 8 + 6 + 5 + 18 + 16 + 15 + 14 + 12 + 10 + 25 + 23 + 22 + 20 + 20 + 42 = 256 \)[/tex]
- Number of classes: 15
- Mean [tex]\( \frac{256}{15} \approx 17.07 \)[/tex]

- Seaside School: Similarly, calculate the mean for Seaside School.
- Seaside School class sizes: 5, 8, 10, 11, 12, 15, 16, 18, 25, 25, 27, 27, 28, 30, 36
- Sum of Seaside School class sizes: [tex]\( 5 + 8 + 10 + 11 + 12 + 15 + 16 + 18 + 25 + 25 + 27 + 27 + 28 + 30 + 36 = 293 \)[/tex]
- Number of classes: 15
- Mean [tex]\( \frac{293}{15} \approx 19.53 \)[/tex]

2. Median
- The median is the middle value of the ordered data set.
- Bay Side School:
- Ordered class sizes: 5, 6, 8, 10, 12, 14, 15, 16, 18, 20, 20, 22, 23, 25, 42
- The median is the 8th number: 16.0 (since there are 15 numbers, the median is the middle one, which is the 8th here)

- Seaside School:
- Ordered class sizes: 5, 8, 10, 11, 12, 15, 16, 18, 25, 25, 27, 27, 28, 30, 36
- The median is the 8th number: 18.0

Hence, the measures of center are:

- Bay Side School: Mean ≈ 17.07, Median = 16.0
- Seaside School: Mean ≈ 19.53, Median = 18.0

### Part B: Calculate the measures of variability

1. Standard Deviation
- Bay Side School: Standard deviation is a measure of how spread out the numbers are.
- Standard Deviation ≈ 8.96

- Seaside School: Similarly,
- Standard Deviation ≈ 9.03

2. Range
- The range is the difference between the highest and lowest values.
- Bay Side School:
- Highest value: 42
- Lowest value: 5
- Range = 42 - 5 = 37

- Seaside School:
- Highest value: 36
- Lowest value: 5
- Range = 36 - 5 = 31

Hence, the measures of variability are:

- Bay Side School: Standard Deviation ≈ 8.96, Range = 37
- Seaside School: Standard Deviation ≈ 9.03, Range = 31

### Part C: If you are interested in a smaller class size, which school is a better choice for you? Explain your reasoning.

If you are interested in a smaller class size, you should consider:

- Mean Class Size: The mean class size at Bay Side School (≈ 17.07) is smaller than that at Seaside School (≈ 19.53).
- Median Class Size: The median class size at Bay Side School (16.0) is also smaller than that at Seaside School (18.0).

Therefore, Bay Side School is a better choice if you are looking for smaller class sizes because both the mean and median class sizes at Bay Side School are smaller compared to those at Seaside School.