Question 1037650
nCx and c(n,x) mean the same thing.
they are the combination formula that tells you how many sets of x out of n you can get where order doesn't matter.


the formula for nCx or c(n,x) is n! / (x! * (n-x)!)


the formula for the probability of x successes out of n possibilities is:


p(x) = c(n,x) * p^x * q^(n-x)


p(x) is the probability of x successes.
c(n,x) is the combination formula of how many sets of x you can get out of n possible choices.
p^x is the probability of success raised to the power of x.
q is the probability of failure raised to the power of (n-x).


q is equal to 1 - p.


when p = .3, q = .7
when p = .5, q = .5
when p = .6, q = .4


not being able to see the graphs, i'm not exactly sure what you are looking at.


the mean is usually n*p
the standard deviation is usually sqrt(n*p*q)
the variance is usually the square of the standard deviation = n*p*q


if you can send me a picture of the graphs and possibly the complete wording of the problem i might be able to figure it out.