Question

Assume that when adults with smartphones are randomly selected, 39% use them in meetings or classes. If 5 adults smartphone users are randomly selected, find the probability that exactly 2 of them use their smartphones in meetings or classes.

Answer 1

Binomial Distribution is being used to solve this problem.

Binomial Distribution

If 'X' is the random variable representing the number of successes, the probability of getting ‘r’ successes and ‘n-r’ failures, in 'n' trails, ‘p’ probability of success ‘q’=(1-p) is given by the probability function

Given,

39% randomly selected  of adults with smartphones use them in meetings or classes.

Probability of a randomly selected adults with smartphones  use them in meetings or classes: p = 39/100 = 0.39

q = 1-p = 1-0.39=0.61

Number of random selected adult smart phone users :n = 5

X: Number of adults smartphone users, use their smartphones in meetings or classes

By binomial probability distribution,

Probability of 'r' adults smartphone users, use their smartphones in meetings or classes from 5 adult smart phone users =

Probability that exactly 2 of them use their smartphones in meetings or classes = P(X=2)

P(X=2) = 0.345238101

Probability that exactly 2 of them use their smartphones in meetings or classes = 0.345238101