40,39,37,33,26,15,

• I THINK ANSWER IS -1
  
  Soln: it forms triangular pattern soln like
  
  40 39 37 33 26 15
  1 2 4 7 11
  1 2 3 4
  1 1 1
  
  so, 1+4+11= 16 and 15-16 = -1
• 11 years agoHelpfull: Yes(57) No(6)
• Guys this is the right solution, check it.
  first, find the diff. like this,
  40-39 = 1
  39-37 = 2
  37-33 = 4
  33-26 = 7
  26-15 = 11
  
  now we got a series 1,2,4,7,11
  1+1 = 2
  2+2 = 4
  4+3 = 7
  7+4 = 11
  next one should be,
  11+5 = 16
  
  Here, the answer should provide 16 if it is subracted by last number in given series,
  15 + 16 = 31 which says 31-15 = 16.
  
  Ans = 31.
  
  
  
• 11 years agoHelpfull: Yes(22) No(32)
• small mistake,
  sry guys omit the last step in ma previous answer ,
  
  Here, the answer should provide 16 if it is subracted by last number in given series,
  15 - 16 = -1 i.e its becoz the series is in decreasing order.
  
  Ans = -1
• 11 years agoHelpfull: Yes(18) No(3)
• 40-39-37-33-26-15-?
  diff= 1,2,4,7,11,?
  again diff of diff= 1,2,3,4,so next one is 5
  so 11+5=16
  and then 15-16=-1ans
• 11 years agoHelpfull: Yes(12) No(3)
• sorry previous soln is wrong!!!
  
• 11 years agoHelpfull: Yes(1) No(6)
• -1
  figure out the difference between the consecutive numbers
  1,2,4,7 -equation 1
  now 1+1=2
  2+2=4
  4+3=7
  7+4=11
  11+5=16
  hence the equation1 would be
  1,2,4,7,11,16
  now the difference between 15 and the required no must be 16
  may be the answer can be 31 but sice the series is decreasing in nature hence the required number to be -1 makes more sense.
• 6 years agoHelpfull: Yes(1) No(0)
• ans is 1
  40,39,37,33,26,15,?
  subtracting 1st no. to 2nd no.
  1 2 3 4 7 11
  again subtracting
  1 2 3 4 5
• 11 years agoHelpfull: Yes(0) No(22)
• 40-39=1
  39-37=2
  add the diff 2+1=3 + 1=4
  so
  37-4=33
  next 4+2(previous difference)=6+1=7
  so now
  33-7=26
  
  now 7+4=11 + 1=12
  ans is
  15-12=3
  
  so ans is 3
• 11 years agoHelpfull: Yes(0) No(13)
• 39-33-15 are the no they can be devided by 3. but 40-37-26-? at the ? mark 13 bz,aft. 39, 37 is an prime no. & aft.15 13 is a prime no.
• 11 years agoHelpfull: Yes(0) No(4)
• -1....as series in decreasing order
• 11 years agoHelpfull: Yes(0) No(1)
• There is a property of series,which is series having nested series in it...we can solve it this way
  40 39 37 33 26 15
  -1 -2 -4 -7 -11(subtracting from 1st term to 2nd term)
  1 2 3 4 (subtracting from 1st term to 2nd term)
  -1 -1 -1 (subtracting from 1st term to 2nd term)
  0 0 (subtracting from 1st term to 2nd term)
  
  now adding all last terms of the series=0+(-1)+4+(-11)+15=7
  so the next term is 7
  
• 11 years agoHelpfull: Yes(0) No(6)
• 40(-1), 39(-2), 37(-4), 33(-7), 26(-11),15
  1, 1(+1)=2, 2(+2)=4, 4(+3)=7, 7(+4)=11
  so next term should be 15(-(11(+5)))=-1
  
• 8 years agoHelpfull: Yes(0) No(1)
• 11
  40-37=3
  37-26=9
  26-a=15
  a=11
• 6 years agoHelpfull: Yes(0) No(0)