Answer: 0.9617
Step-by-step explanation:
Given : The proportion of adults use their phones in meetings or classes : p=0.57
Number of adults randomly selected : n= 9
Let x be the random variable that represents the number of adults use their phones in meetings or classes.
By using binomial probability formula, to find the probability of getting success in x trials.
The probability that at least 3 of them use their smartphones in meetings or classes will be :-
Hence, the required probability is 0.9617 .