Question 1152070: According to StatsSa, the unemployment rate in South Africa as of 2018 has risen to 28%. For randomly selected group consisting of eight South Africans, what is the probability that at least two are unemployed?
Answer by ikleyn(52780)   (Show Source):
You can put this solution on YOUR website! .
This is a binomial distribution type problem, where the probability under the question is the sum
P =  (1)
The number of trials is 8;
The indexes of success trials k = 2,3,4,5,6,7,8
The probability of success trial p = 0.28;
q = 1 - p
C(n,k) = n! / (k! * (n-k)!) are binomial coefficients.
The sum (1) is equal to 1 -  . (2)
You may calculate each term in (2) individually and then sum them up.
Or, alternatively, you may use Excel function BINOM.DIST(1, 8, 0.28, TRUE) to calculate the cumulative sum value
 = 0.296906.
In this way, the value of (2) is equal to 1 - 0.296906 = 0.703094 (approximately). ANSWER
Thus the problem is solved using Technology.
-------------
On Excel function BINOM.DIST, see its description everywhere, for example
https://support.office.com/en-us/article/binom-dist-function-c5ae37b6-f39c-4be2-94c2-509a1480770c
|
|
|
