00:01
Hey there, welcome to numerade.
00:03
So we're looking at a textbook here, counting the number of letters that contains in each word.
00:10
So we randomly choose 20 words from a textbook, from page of a textbook, and we're asked to construct a 98 % confidence interval.
00:19
So for our confidence interval here, we will need to use this data that is given to us and find our sample mean and standard deviation first.
00:28
So we take the sum of x divided by our sample size 20, which gives us a mean of around 5 .5.
00:41
For our sample standard deviation, we're going to be taking the square root of our sum of squares divided by our sample size minus 1.
01:05
So we have 20 minus 1, which gives us a standard deviation of around.
01:16
So we calculate standard duration of around 2 .69 or 2 .7...