What is the next number? 3,-6,12,4,20

Answer 1

3 - 9 = -6

-6 + 18 = 12

12 - 8 = 4

4+ 16 = 20

THe pattern is take away 9, add 18, take away 8, add 16, ...

so it takes away 9,8,7,6,5,.... but adds 18,16,14,12,... AFTER

that is it ALTERNATES subtraction and addition

SO the next step is to subtract 7: 20 - 7 = 13

THen adds 14, so 13+14 = 27

SPECIFICALLY.,

THe sequence is 3

subtracts 9: -6

adds 18 : 12

subtracts 8: 4

adds 16: 20

subtracts 7: 13

adds 14: 27

subtracts 6: 21

adds 12: 33

subtracts 5: 28

adds 10: 38

subtracts: 4: 34

adds 8 42

subtracts 3: 39

adds 6 45

subtracts 2: 43

adds 4 47

subtracts 1 46

adds 2 48

subtracts 0 48

adds 0 48

subtracts -1 49 <--- same as adding 1; will be written as such henceforth; adds 1 from now on

adds -2 47 <--- same as subtract 2; will be written as such henceforth; subtracts 2 from now on

ADDS 2 49

SUBTRACTS 4 45 <--- net result is -2

adds 3 48

subtracts 6 42 <--- net result is -3

adds 4 52

subtracts 8 44 <--- net result is -4

adds 5 49

subtracts 10 39 --> net result is -5

it will end up being 33, 26, 18, 9, -1, -12, -25, .....

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