Posted by jimmy on Sunday, July 22, 2012 at 5:11pm.
Use binomial theorem with N=5, p=0.70
=> q=1-p=0.3
Let
C(n,r)=binomial coefficient=n!/(r!(n-r)!)
(a) all five resolved
P(X=5)=C(5,5)p^5q^0=1*0.7^5*1=0.17
(b) at least one not resolved
i.e. not all five
P(X≤4)=1-P(X=5)
(c) none resolved
P(X=0)=C(5,0)p^0q^5=1*1*0.3^5=0.002
(d) at least one resolved
i.e. not none resolved
P(X≥1)=1-P(X=0)
A little suggest for follow-ups to my responses.
Start with a follow-up to the original post. If your patience runs out, then start a new post with or without the recipient's name under "school subject".
Assuming you have no problem with parts (a) and (c), parts (b) and (d) are simply the complement to the preceding part.
For example,
P(X≤4) means P(X=0)+P(X=1)+P(X=2)+P(X=3)+P(X=4).
However, we make use of the fact that the sum of probabilities of all possible events add up to 1, or
P(X=0)+P(X=1)+P(X=2)+P(X=3)+P(X=4)+P(X=5)=1 (all possible events), so by transposition, we obtain:
P(X=0)+P(X=1)+P(X=2)+P(X=3)+P(X=4)
=1-P(X=5)
as was done in (b) and (d).
Related Questions
math-please help! - The number of complaints received by a business bureau can ...
statistics - this is to mathmate...this is jimmy and you answered by questions ...
business - If you think that your bill is wrong, you should first: A. contact ...
statistics - Consumer Reports rated airlines and found that 80% of flights ...
Statistics Question - Consumer Reports rated airlines and found that 80% of ...
Statistics - A consumer protection group reports that 25% of 5-lb bags of sugar ...
Economics - The Bureau of Labor Statistics follows five steps to calculate ...
marketing - can you help me understand these better please o Consumer ...
statistics - Suppose the number of customer complaints per day on the morning ...
Statistics - A national survey of small businesses reports that 70% of all small...
For Further Reading
