Question

an app estimates phone usage by counting the number of times a phone screen is unlocked during the course of a day. a sample of 25 users is shown. complete parts a through c below.
123 65 119 145 114
125 114 91 113 125
88 141 105 116 121
186 136 65 128 107
97 126 101 90 10

a. what is the mean and standard deviation?
the mean is
(round to the nearest hundredth as needed.)

Explanation:

Step1: Count the number of data points

We have 25 data points (since it's a sample of 25 users).

Step2: Sum all the data values

Let's list out all the data values: 123, 65, 119, 145, 114, 125, 114, 91, 113, 125, 88, 141, 105, 116, 121, 186, 136, 65, 128, 107, 97, 126, 101, 90, 10.

Now, sum them up:

$$
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$$

Step3: Calculate the mean

The mean \(\bar{x}\) is given by the formula \(\bar{x} = \frac{\sum_{i = 1}^{n} x_i}{n}\), where \(n = 25\) and \(\sum_{i = 1}^{n} x_i = 2751\).

So, \(\bar{x} = \frac{2751}{25} = 110.04\)

Answer:

The mean is \(\boxed{110.04}\)