SOLUTION: Next number in sequence 3, -6 , 12, 4, 20 7, 16, 8, 27, 9 2, 7, 26, 101, 400 7, 21, 8, 72, 9

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Question 845949: Next number in sequence
3, -6 , 12, 4, 20
7, 16, 8, 27, 9
2, 7, 26, 101, 400
7, 21, 8, 72, 9
Answer by AnlytcPhil(1806)   (Show Source): You can put this solution on YOUR website!
3, -6 , 12, 4, 20 

Start with 3

 3 -  9 = -6
-6 + 18 = 12
12 -  8 =  4
 4 + 16 = 20
20 -  7 = 13
13 + 14 = 27
27 -  6 = 21

-----------------

7, 16, 8, 27, 9 

7
2×8 = 16
8
3×9 = 27
9
4×10 = 40
10
5×11 = 55

------------------

7, 26, 101, 400

Start with 7

  7×4-2 =   28-2 =  26
 26×4-3 =  104-3 = 101
101×4-4 =  404-4 = 400
400×4-5 = 1600-5 = 1595 

-------------------

7, 21, 8, 72, 9

Start with 7
 7
 7×31 =   7×3 =  21
 8 
 8×32 =   8×9 =  72
 9
 9×33 =  9×27 = 243
10
10×34 = 10×81 = 810

Edwin
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