The name “The Binomial Distribution” is derived from the binomial expansion, because if you use the formula for binomial expansion,
you can substitute
and
and then the probability of obtaining
successes in
attempts is given by the
th term![]()
There are three conditions necessary for the binomial to be a possible distribution.
-
is a fixed number. There are
trials or attempts. -
is fixed throughout the process. -
Each trial is independent of any other trial.
The notation for the Binomial distribution is![]()
Example: A fair dice is thrown 10 times. Find the probability of
a)Throwing 3 sixes.
b)Throwing at most 1 six.
c)Throwing at least 1 six.
a)The probability of throwing a six is
to 4dp.
b)
to 4 dp.
c)
to 4 dp.
Intuitively, if
attempts take place and the probability of success is
the expected number of successes is![]()