9 12 4 8 12 15 5 9 -3 6 2 6 6 -9

• 9 12 4 8 12 15 5 9 -3 6 2 6 6 -9 -3
  + / + + + / + + + / + + + /
  3 3 4 4 3 3 4 -12 9 3 4 0 -15 3
  here / after +++ nd all / by 3 so
  when we (-9/3=-3)
  ans=-3
• 11 years agoHelpfull: Yes(10) No(18)
• Ans -3
  ---------------------------------------------------------------------------------------------------------------------------------------------
  Divide the Series into sets of two numbers
  
  (9,12) Diff 3 Divide the Second number by 3 to get the first number in next set(12/3=4)
  (4,8) Diff 4
  (12,15) Diff 3 Divide the Second number by 3 to get the first number in next set(15/3=5)
  (5,9) Diff 4
  (-3,6) Diff 3 Divide the Second number by 3 to get the first number in next set(6/3=2)
  (2,6) Diff 4
  (6,-9) Diff 3 Divide the Second number by 3 to get the first number in next set(-9/3=-3)
  ---------------------------------------------------------------------------------------------------------------------------------------------
  So Answer is -3
  
  
• 9 years agoHelpfull: Yes(1) No(1)
• 115-100=-15
  100-86=-14
  86-74=-12
  74-65=-9
  65-60=-5
  -15+1=-14
  -14+2+-12
  -12+3=-9
  -9+4=-5
  -5+5=0
  ans is 60+0=60
• 10 years agoHelpfull: Yes(0) No(6)
• 
  Answer should be 9
• 7 years agoHelpfull: Yes(0) No(0)