12.4.3

Section 12.4.3 Blog Entry

Having read section 12.4.3 in the text:

Difficult:
I was a little confused on page 832 when the text explained that "as all outcomes ar equally likely, we find P(S(5-subscript) =3) ...." if S(n-subscript)=number of successes in n trials. Since the definition of S(n-subscript) was given first, I understood it to be true, but when looking at the example, it said that out of five trials, there were three successes (or 1's). If this is true, then shouldn't S have a 3-subscript rather than a 5-subscript?

On page 833, in example 20, I was a bit confused as to why ther (n-k) exponent was not accounted for in the solution. I think since (1-p) is raised to the (n-k) power in the formula, the (1- .5) should be raised to the (.5-3) power in the solution.

Reflective:
It kind of felt as if this section on binomial distribution should have been included before the previous section about mean and variance and discrete distributions. It seems more pertinent to the probabilities, combinations, and permutations section in the previous section 3 of chapter 12. I think this section 12.4.3 was much more straightforward than the previous two sections since it involved applying and using the given definitions and equations of the section to each individual problem.