00:01
Welcome to this lesson.
00:03
In this lesson we have a survey that reports 59 % of americans had seen a drone in action.
00:14
So we sample 50 americans randomly and we are looking at the probability that more than 30 have seen a drone.
00:24
So this is a binomial probability with number of trials as 50 the probability of success as 0 .59 and we are looking at more than 30.
00:39
So we can write it in another way as 1 minus the binomial probability still 50 then 0 .59.
00:50
Down here let me bring it down.
00:56
It's equivalent.
01:00
It's 1 minus the binomial probability with 50 trials 0 .59 as the probability of success and we have less than or equals to 30.
01:17
Alright so the two are the same.
01:21
Now let's move to the b part where probability that at least 25 had seen a drone.
01:31
So here we have still with 50 trials the probability of success is 0 .59 and we are looking at at least 25.
01:43
So this is greater than or equals to 25 which we can write as 1 minus the binomial probability.
01:55
Mostly we start from 0 to a certain number.
01:59
So we can take the complementary probability...