Find the missing number in 25,38,____,64,-27,90

• 25,38,-1,64,-27,90
  
  25+38=63
  -1+64=63
  -27+90=63
• 8 years agoHelpfull: Yes(8) No(2)
• Closely analyzing the given series, it follows a pattern as shown below :
  
  25 = 25
  25 + 13 = 25 + 13 = 38
  25 - 13x2 = 25 - 26 = -1 (this is our answer)
  25 + 13x3 = 25 + 39 = 64
  25 - 13x4 = 25 - 52 = -27
  25 + 13x5 = 25 + 65 = 90
• 7 years agoHelpfull: Yes(7) No(0)
• 64-38=26
  25-26=-1
• 8 years agoHelpfull: Yes(2) No(2)
• -1
  38+26=64,64+26=90
  25-26=-1,-1-26=-27
• 8 years agoHelpfull: Yes(2) No(3)
• Take alternate numbers
  i.e., 25, x, -27 and 38, 64, 90
  
  consider 2nd series 38, 64, 90
  38-64 = -26
  64-90 = -26
  
  Now 1st sequence 25, x, -27
  25-x = -26
  x-(-27) = -26
  By solving we get x = -1.
  
  So, the answer is -1.
• 3 years agoHelpfull: Yes(0) No(0)