Find the next number in the series 1, 3 ,7 ,13 ,21 ,31
(a) 43
(b) 33
(c) 41
(d) 45

• (a) 43
  
  Next Number is 43
  Final sequence = 1,3,7,13,21,31,43
  
  Sequence is increasing by +2,+4,+6,+8,+10,+12.
  i.e,
  1 +(2*1) = 3
  3 +(2*2) = 7
  7 +(2*3) = 13
  13+(2*4) = 21
  21+(2*5) = 31
  31+(2*6) = 43
• 12 years agoHelpfull: Yes(3) No(2)
• INCREMENT EACH NUMBER WITH MULTIPLE OF 2
  ans- 43
• 12 years agoHelpfull: Yes(2) No(1)