The list comprises the first 4 numbers of the sequence:
Un = -5n3 + 45n2 - 127n + 126 for n = 1, 2, 3, ...
3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39 . . .
39-15+18 6x3 Answer: 25
15
As the ins are increasing by 1, the outs are increasing by 3. 7 Double + 1 = 15 8 Double + 2 = 18 9 Double + 3 = 21 10 11 12 13 14 15 Double + 9 = 39
3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45.
mean(18, 23, 39, 10, 22, 17, 16, 15) = (18 + 23 + 39 + 10 + 22 + 17 + 16 + 15) ÷ 8 = 160 ÷ 8 = 20
18, 23, 10, 39, 22, 17, 16, 15 Mean = (18 + 23 + 10 + 39 + 22 + 17 + 16 + 15)/8 = 20 Lowest Number in set is 10 Highest Number in set is 39 Range = (39 - 10) = 29
3 6 9 12 15 18 21 24 27 30 33 36 39 42...
It is: 3
The next number could be 26 The next number could be 12 - - - - - - - - - The next number that is in the sequence is 12.
3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42 . . .
12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45, 48