9 3 6 21 9 12 33 15

3*(1+2),3*1,3*2
3*(3+4),3*3,3*4
3*(5+6),3*5,3*6
so 18 is the answer
9 years agoHelpfull: Yes(6) No(0)
9-3 = 6
21-9 = 12
33-15 = 18
so answer is 18.
9 years agoHelpfull: Yes(5) No(1)
(9,3,6)(21,9,12)(33,15,x)
3[(3,1,2)(7,3,4)(11,5,x/3)]
since 1+2=3,3+4=7,5+x/3=11..
so x=18
9 years agoHelpfull: Yes(4) No(0)
the pattern goes like 3*3, 3*1, 3*2, 3*7, 3*3, 3*4, 3*11, 3*5...next will be 3*6
it is like 3 then 1,2, then 3+4, then 3, 4 then 7+4, then 5,6
9 years agoHelpfull: Yes(0) No(0)
18 as 9-3=6
21-9=12 the same way 33-15=18
9 years agoHelpfull: Yes(0) No(0)
(9,3,6)=6+3=9 ....similarly: (33,15,?)=15+?=33

so ?=18
9 years agoHelpfull: Yes(0) No(0)
(9,3,6) --> 9-6=3
(21,9,12) -->21-12=9
(33,15,x)--> 33-x=15, X=18
9 years agoHelpfull: Yes(0) No(0)
3+3=6
9+3=12
15+3=18 ANS
9 years agoHelpfull: Yes(0) No(0)
(9,3,6)=9-3=6
(21,9,12)=21-9=12
(33,15,x)=33-15=18
9 years agoHelpfull: Yes(0) No(0)
series 6,12,18?
9 years agoHelpfull: Yes(0) No(0)
9-3=6
21-9=12
33-15=18
so ans is 18
9 years agoHelpfull: Yes(0) No(0)
ans:18
3*3 , 3, 6 , 3*(3+4) , 9, 12 , 3*(7+4) ,15 , 18
,
9 years agoHelpfull: Yes(0) No(0)
(9-3=6)
(21-9=12)
(33-15=18)
9 years agoHelpfull: Yes(0) No(0)
9-3=6
21-9=12
33-15=18
ans)18
9 years agoHelpfull: Yes(0) No(0)

9,3,6,21,9,12,33,15,?