mandy is working at the zoo. she must record the ages of the tortoises. there are 9 tortoises. their ages…

Explanation:

Step1: Calculate the mean

The formula for the mean $\bar{x}=\frac{\sum_{i = 1}^{n}x_{i}}{n}$, where $x_{i}$ are the data - points and $n$ is the number of data - points. Here, $n = 9$, and $\sum_{i=1}^{9}x_{i}=29 + 2+12 + 26+18+34+54+44+18=237$. Then $\bar{x}=\frac{237}{9}\approx26.33\approx26$.

Step2: Calculate the median

First, arrange the data in ascending order: $2,12,18,18,26,29,34,44,54$. Since $n = 9$ (an odd number), the median is the $\left(\frac{n + 1}{2}\right)$-th value. $\frac{9+1}{2}=5$ - th value, which is $26$.

Step3: Calculate the mode

The mode is the value that appears most frequently in the data - set. The number $18$ appears twice, and all other numbers appear only once, so the mode is $18$.

Step4: Calculate the range

The range is the difference between the maximum and minimum values in the data - set. The maximum value is $54$ and the minimum value is $2$. So the range is $54−2 = 52$.

Answer:

1. B. 26
2. B. 26
3. A. 18
4. D. 52