Assume that when adults with smartphones are randomly selected, 58% use them in meetings or classes. If 7 adult smartphone users are randomly selected, find the probability that at least 2 of them use their
smartphones in meetings or classes.
The probability is
(Round to four decimal places as needed.),

Step-by-step explanation:

The number of adults that use smartphones in meetings or classes follows a binomial distribution. So, the probability that x adults use their  smartphones in meetings or classes is calculated as:

Where, n is the number of identical and independents events, in this case, 7 adults with smartphones. p is the probability of success or the probability that the adult use the smartphone in meeting or classes, in this case, p is equal to 0.58

So, replacing values, we get that the probability that x adults use their  smartphones in meetings or classes is:

Now, the probability that at least 2 of them use their  smartphones in meetings or classes is calculated as:

Where:

Finally, is equal to:

answer:

c. the third graph