The librarian purchased 22 copies of a best-selling book for $385.66.
1 answer:
You might be interested in
Answer:
a)There is a 4.88% probability that none is concerned that employers are monitoring phone calls.
b)There is a 7.89% probability that all are concerned that employers are monitoring phone calls.
c)There is a 37.23% probability that exactly two are concerned that employers are monitoring phone calls.
Step-by-step explanation:
The binomial probability is the probability of exactly x successes on n repeated trials in an experiment which has two possible outcomes (commonly called a binomial experiment).
It is given by the following formula:
In which is the number of different combinatios of x objects from a set of n elements, given by the following formula.
And p is the probability of a success.
In this problem, a success is being concerned that employers are monitoring phone calls.
53% of adults are concerned that employers are monitoring phone calls, so
(a) Out of four adults, none is concerned that employers are monitoring phone calls.
Four adults, so .
Is the probability of 0 successes, so x = 0.
There is a 4.88% probability that none is concerned that employers are monitoring phone calls.
(b) Out of four adults, all are concerned that employers are monitoring phone calls.
Four adults, so .
Is the probability of 4 successes, so x = 4.
There is a 7.89% probability that all are concerned that employers are monitoring phone calls.
(c) Out of four adults, exactly two are concerned that employers are monitoring phone calls.
Four adults, so .
Is the probability of 4 successes, so x = 2.
There is a 37.23% probability that exactly two are concerned that employers are monitoring phone calls.