all 150 eighth - grade students at a local middle school were asked how many hours they studied. each row of…

all 150 eighth - grade students at a local middle school were asked how many hours they studied. each row of the table represents one sample from the population. find the mean of each sample.\npopulation data\nrow 1 6 5 3 0 4\nrow 2 4 5 3 5 6\nrow 3 7 1 4 5 3\nrow 4 4 2 5 6 3\nwhich row has the greatest mean?\nrow 1\nrow 2\nrow 3\nrow 4
Answer
Explanation:
Step1: Recall mean formula
The mean $\bar{x}=\frac{\sum_{i = 1}^{n}x_{i}}{n}$, where $n$ is the number of data - points and $\sum_{i = 1}^{n}x_{i}$ is the sum of the data - points. Here $n = 5$.
Step2: Calculate mean for Row 1
$\sum_{i=1}^{5}x_{i}=6 + 5+3 + 0+4=18$. Mean of Row 1, $\bar{x}_1=\frac{18}{5}=3.6$.
Step3: Calculate mean for Row 2
$\sum_{i = 1}^{5}x_{i}=4 + 5+3 + 5+6=23$. Mean of Row 2, $\bar{x}_2=\frac{23}{5}=4.6$.
Step4: Calculate mean for Row 3
$\sum_{i = 1}^{5}x_{i}=7 + 1+4 + 5+3=20$. Mean of Row 3, $\bar{x}_3=\frac{20}{5}=4$.
Step5: Calculate mean for Row 4
$\sum_{i = 1}^{5}x_{i}=4 + 2+5 + 6+3=20$. Mean of Row 4, $\bar{x}_4=\frac{20}{5}=4$.
Answer:
B. Row 2