assume that when adults with smartphones are randomly selected, 54% use them in meetings or classes (based on data from an LG Smartphone survey). If 8 adult smartphone users are randomly selected, find the probability that exactly 6 of them use their smartphones in meetings or classes.

Respuesta :

Step-by-step explanation:

Given:

p=54 %=0.54  

n=8

DEFINITIONS

Definition binomial probability:  

[tex]P(X=x)=\frac{n !}{x !(n-x) !} \cdot p^{x} \cdot(1-p)^{n-x}[/tex]

Complement rule:

P( not A) = 1- P(A)

[tex]Addition rule for disjoint or mutually exclusive events[/tex]

[tex]P(A \text { or } B)=P(A)+P(B)[/tex]

Evaluate the definition of binomial probability at x=6

[tex]P(X=6)=\frac{8 !}{6 !(8-6) !} \cdot 0.54^{6} \cdot(1-0.54)^{8-6}=28 \cdot 0.54^{6} \cdot 0.46^{2} \approx 0.1469[/tex]