00:01
So in this one we want the mean median mode, the first quartile, the third core tile, and the 90th percentile.
00:09
So to do that, we need our data in order.
00:11
So 42, 53, 54, 61, 61, 61, 62, 62, 63, 64, 66, 62, 63, 64, 66, 66, 67, 68, 69, 69, 71 71 76 78 88 81 83 well the mean add them all up you get 1 ,3 318 divide by 20 data values that's 69 the median is the exact middle number for the median there's 20 numbers so 1, 2, 4, 5, 6, 7, 8, 10 is between 66 and 67.
01:23
So we take 66, 66 62, we get 66.
01:33
The mode is the most frequent number.
01:38
So the mode is 60.
01:40
There's three of them.
01:48
First quartile, we call q1.
02:03
Well, if we take 0 .25 times 21, that's the n plus 1 in your book, we get 5 .25...