What is the sequence 3, -6, 12, 4, 20, ?

Answer 1

i'm in agreement with the other tutor that it's not really clear what the pattern is between these terms! did it give you any more context as to what the values were on the other side? or are you learning about a particular type of sequence in your course? :)

Answer 2

Best guess is 13

after trying a few things, that don't really work

the ratio of a term to its prior term is -2, -2, 1/3, 5

2, 3, 5 is a fibonacci sequence.

3(-2) = -6

-6(-2) = 12

12/3 = 4

4(5) = 20

the 6th term could be just about anything.

but if the next term's ratio followed the fibonacci sequence, an 8 would show up, either as 1/8 x 20 or 8 x 20, so maybe 160?

I hope someone else answers this question, as its not obvious, whatever the correct answer is

another alternative is look at the arithmetic differences, -9, 18, -8, 16

that looks more promising, guess would be -7, 14 as the next two ratios, alternating signs and reducing the 9 to 8 to 7.

20-7 = 13 for the 6th term

then 13+14 = 27 for the 7th term