3, 22 , 7, 45, 15, ? , 31
(a) 45 (b) 90 (c) 91 (d) 35

• 91 should be the answer......
  3*2 + 1 = 7 the digit one after other.
  22*2 + 1 = 45.
  same as 45*2 +1 = 91.
• 13 years agoHelpfull: Yes(40) No(0)
• 3*2 + 1 = 7
  22*2 + 1 = 45
  45*2 +1 = 91
• 12 years agoHelpfull: Yes(6) No(0)
• it seems i cant post formulas on this page....
  sorry about the upper block_:(
• 11 years agoHelpfull: Yes(2) No(1)
• I have done it in my OWN way....
  3 22 7 45 15 ?-->[91]
  / / / / /
  + + + + +
• 11 years agoHelpfull: Yes(0) No(3)
• 91..........
• 8 years agoHelpfull: Yes(0) No(1)
• (c) 91
  here 1st value is 3
  2nd value is 22
  3rd value is (3*2)+1=7
  4th value is (22*2)+1=24
  5th value is (7*2)+1=15
  6th value is (45*2)+1=91
  7th value is (15*2)+1=31
• 8 years agoHelpfull: Yes(0) No(0)