00:01
This problem we're told that we have a binomial distribution where p is 0 .3, and n is 14.
00:08
Now before we find what we're looking for, remember this means the probability.
00:13
The probability of x is 14 choose x times 0 .3 to the x times 0 .7 to the 14 minus x.
00:25
Now let's find what we're looking for here.
00:28
First you want the probability that we have 7 successes.
00:32
So the probability of 7 just means we plug in 7 for x.
00:36
This is 14 to 7 times 0 .3 to the 7 times 0 .7 to the 14 minus 7, which is also 7.
00:49
Now we just need to type this in.
00:50
In your calculator, you can do the 14 -2 -7 under ncr, which is the ncr button...