Question

Suppose 80% of all students use Snapchat. In a random sample of 10 students:

What is the probability 8 of these students use Snapchat?

What is the probability more than 6 of these students use Snapchat

Answer 1

We have here,

n=10 , p = 0.80

Consider , X= students use Snapchat.

i) The probability 8 of these students use Snapchat

P[X=8] = C(10,8)*(0.80)^8*(1-0.80)^2

=0.3020

ii) The probability more than 6 of these students use Snapchat

= 1-0.1209....................by using =BINOMDIST(6,10,0.8,TRUE)

=0.8791