Question

Assume that when adults with smartphones are randomly​ selected, 48​% use them in meetings or classes. If 55 adult smartphone users are randomly​ selected, find the probability that at least 22 of them use their smartphones in meetings or classes.

Answer 1

This is a problem of Binomial Probability.

Success Rate = p = 0.48
Sample Size = n = 55
Number of success = x = 22

We are to find $P(X \geq 22)$ i.e. that probability that atleast 22 adults use the smartphone in meetings or class.

The probability can be calculated using the Binomial Calculators and it comes out to be 0.907.

This means there is 0.907 or 90.7% probability that there are atleast 22 adults among the 55 selected adults who use cell phones in meeting or class.