It’s about statistics

Question

ssume that when adults with smartphones are randomly​ selected, 62​% use them in meetings or classes. If 15 adult smartphone users are randomly​ selected, find the probability that exactly 10 of them use their smartphones in meetings or classes.

Answer 1

There are two ways to solve this.

One is to use the formula

P(x) = C(n,x)p^x(1-p)^n-x

In this case, n = 15, x = 10, and p = .62, so C(15,10).62¹⁰(1-.62)^15-10 =

C(15,10).62¹⁰(.38)⁵=

3003(.008393)(.007924) =.199706

The other way is to plug n, x, and p into Excel or a statistical calculator's binomial formulat

In Excel, we use binom.dist(10,15,.62,0)

The 0 is for P(x), or the probability mass function; with 1, you get F(x), P(X <= x)

The solution is .199706, the same as above.