Question

the responses of a sample of 1030 people who were asked if the air quality in their community is better or worse than it was 10 years ago are show below. better: 341 worse: 440 same: 249

Explanation:

Step1: Recall mean formula

The mean of a set of numbers $x_1,x_2,\cdots,x_n$ is $\bar{x}=\frac{\sum_{i = 1}^{n}x_i}{n}$. Here $n = 3$, $x_1=341$, $x_2 = 440$, $x_3=249$.

Step2: Calculate sum

$\sum_{i=1}^{3}x_i=341 + 440+249=1030$.

Step3: Calculate mean

$\bar{x}=\frac{1030}{3}\approx343.333$.

Answer:

$343.333$