Question

Assume that when adults with smartphones are randomly​ selected, 57​% use them in meetings or classes. If 8 adult smartphone users are randomly​ selected, find the probability that exactly 2 of them use their smartphones in meetings or classes.

Answer 1

Answer: 0.0575

Explanation:

Binomial probability distribution :-

`P(x)=^nC_xp^x(1-p)^(n-x)`, where P(X) is the probability of getting success in x trials, n is the total number of trials and p is the probability of success in each trial ( in decimal ).

Given : The probability that adults use smartphones in meetings or classes = 0.57

Sample size : n= 8

Now, the probability that exactly 2 of them use their smartphones in meetings or classes :-

`P(x)=^8C_2(0.57)^2(0.43)^(6)\\\\=(8!)/((8-2)!2!)(0.57)^2(0.43)^(6)\\\\=0.0575067039294\approx0.0575`

Hence, the required probability = 0.0575