select the correct answer. in an attempt to be environmentally friendly, the city council decides that there…

select the correct answer. in an attempt to be environmentally friendly, the city council decides that there must be at least 18 trees on each block in the city. a sample of 20 blocks was randomly surveyed, with these results (number of trees per block): 24, 17, 7, 20, 28, 27, 10, 21, 30, 8, 30, 27, 22, 27, 27, 13, 27, 20, 24, 17. what is the sample mean number of trees per block $\bar{x}$? a. there is insufficient data to answer this question. b. 17.7 c. 21.3 d. 24

select the correct answer. in an attempt to be environmentally friendly, the city council decides that there must be at least 18 trees on each block in the city. a sample of 20 blocks was randomly surveyed, with these results (number of trees per block): 24, 17, 7, 20, 28, 27, 10, 21, 30, 8, 30, 27, 22, 27, 27, 13, 27, 20, 24, 17. what is the sample mean number of trees per block $\bar{x}$? a. there is insufficient data to answer this question. b. 17.7 c. 21.3 d. 24

Answer

Explanation:

Step1: Recall sample - mean formula

The formula for the sample mean $\bar{x}=\frac{\sum_{i = 1}^{n}x_{i}}{n}$, where $n$ is the sample size and $x_{i}$ are the individual data - points.

Step2: Identify $n$ and sum the data

Here, $n = 20$, and the data points are $24,17,7,20,28,27,10,21,30,8,30,27,22,27,27,13,27,20,24,17$. $\sum_{i = 1}^{20}x_{i}=24 + 17+7+20+28+27+10+21+30+8+30+27+22+27+27+13+27+20+24+17$ $=426$.

Step3: Calculate the sample mean

$\bar{x}=\frac{\sum_{i = 1}^{20}x_{i}}{n}=\frac{426}{20}=21.3$.

Answer:

C. 21.3