Historical data indicates that only 20% of cable customers are willing to switch companies. if a binomial process is assumed, then in a sample of 20 cable customers, what is the probability that no more than 3 customers would be willing to switch their cable?
a. 0.15
b. 0.411
c. 0.85
d. 0.20

= =0.4114

Explanation:

Given that ;

p=0.20

n = 20

Therefore we can compute the probability as;

where,

P[X=0] = 0.0115

P[X=1] = 0.0576

P[X=2] = 0.1369

P[X=3] = 0.2054

Therefore;

=0.0115+0.0576 +0.1369 + 0.2054  

=0.4114

two years ago, when picking flowers in the mountains back of yosemite valley, i found a book. it was blotted and storm-beaten; all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however; many of the inner pages were well preserved. and although all were more or less stained and torn, whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today; its granite pages have been torn and blurred by the same storms that wasted the castaway book.

two years ago, when picking flowers in the mountains back of yosemite valley; i found a book. it was blotted and storm-beaten, all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however, many of the inner pages were well preserved. and although all were more or less stained and torn; whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today, its granite pages have been torn and blurred by the same storms that wasted the castaway book.