Question

what is the mean? if the answer is a decimal, round it to the nearest tenth. 97 80 88 87 84 99 89 91

Explanation:

Step1: Sum up the numbers

$$97 + 80+88 + 87+84 + 99+89+91$$
$$=(97 + 80)+(88 + 87)+(84 + 99)+(89 + 91)$$
$$=177+175+183+180$$
$$=(177 + 175)+(183 + 180)$$
$$=352+363$$
$$=715$$

Step2: Count the number of data points

There are \(n = 8\) data points.

Step3: Calculate the mean

The formula for the mean \(\bar{x}=\frac{\sum_{i = 1}^{n}x_{i}}{n}\). Substitute \(\sum_{i=1}^{n}x_{i}=715\) and \(n = 8\) into the formula: \(\bar{x}=\frac{715}{8}=89.375\)

Step4: Round to the nearest tenth

To round \(89.375\) to the nearest tenth, look at the hundredth - digit. The hundredth - digit is \(7\). Since \(7\gt5\), we round up the tenth - digit. So \(89.375\approx89.4\)

Answer:

\(89.4\)