3, 12, 7, 26, 15? a) 54 b) 27 c) 108 d) 31

• ans=b)54
  take odd nos 3,7,15 the diffrence of the nos are coming by 4 multiplication 4,8,...
  tak even nos 12,26 the difference of the nos are coming by 14 muliplication 14, the next is 28
  so add 26+28
  54 ans is
• 12 years agoHelpfull: Yes(4) No(0)
• 1st series =3, 7, 15
  2nd series =12,26, ?
  in 1st series = 7(3*2+1) & 15=(7*2+1)
  similarly in 2nd series ----> 26=(12*2+2) so...?=(26*2+2)
  and answer is=54...........
• 12 years agoHelpfull: Yes(3) No(0)