Sorted sample : 10, 12, 15, 16, 20, 20, 25, 80
Since there is significant mass near 10 (at 12) I would not exclude 10 as an outlier.
Similarly there is significance mass just below 25 at 20, and I would not exclude 25 either.
However, 80 is quite distant from the median at 18 and might be an outlier. In contrast, 18-10=8 and 25-18=7; these sample items are comparably close to the median.
By usual definitions of outliers, there is none.
For the numbers 18, 16, 15, 12, 10 the LCM is: 720
252.
Mean: 11.6 Median: 12 Mode: 10, 12, 15, 16, 5 Range: 11
6
16
(21+15+19+28+10+17+9+15+26+14+10+18+24+12+16) / 15 = 16.93 recurring (that is, 16.93333...)
240
10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20
Range = Maximum - Minimum = 20 - 8 = 12.
It is 13.5 which is the value halfway between the two middle values 12 and 15.
10, 12, 14, 15, 16, 18, 20.