4. what is the next number?

what is the 12th number?

1, 3,9,27,81,


5.what is the next number?
what is the 7th number?

160, 80, 40 ,20 ,10,


Sagot :

1,3,9,27,81, ___, ____
Pattern:  the next number is 3 times the previous number.
  3 (81) = 243  (6th number/term)
  3 (243) = 729 (7th number/term)

Do the same to get the 12th number.  (This is not arithmetic sequence, where the difference is common between any two consecutive numbers in a sequence).

You can do it :-)

160, 80, 40, 20, 10, ___,  ____.
Pattern:  The next number is half (1/2) of the previous number/term
1/2(10) = 5  (6th number/term)
1/2 (5)  = 2[tex] \frac{1}{2} [/tex] or 2.5  (7th number/term)