3, 22 , 7, 45, 15, ? , 31

(a) 45 (b) 90 (c) 91 (d) 35

• 3*2+1=7
  7*2+1=15
  15*2+1=31
  similarly
  22*2+1=45
  45*2+1=91
  ans: c
• 14 years agoHelpfull: Yes(5) No(0)
• ans is c)91
  split the eqn like
  3 7 15 31
  22 45 ?
  
  3*2+1=7
  7*2+1=15
  15*2+1=31
  
  22*2+1=45
  like wise 45*2+1=91
  
  
• 14 years agoHelpfull: Yes(3) No(0)
• simply use fibanoci series for alternate numbers
  for 3 7 15
  3+4=7, 7+8=15, 15+16=31
  similarly
  22+23=45 45+46=91
  answer is 91
• 14 years agoHelpfull: Yes(1) No(1)
• the answer is 91.
  
• 13 years agoHelpfull: Yes(0) No(0)
• the answer is 91.
  
• 13 years agoHelpfull: Yes(0) No(0)
• 91
• 6 years agoHelpfull: Yes(0) No(0)