3,5,8,13,22,__

• answer is 39
  
  5=3*2-1
  8=5*2-2
  13=8*2-3
  22=13*2-4
  39=22*2-5
  
• 12 years agoHelpfull: Yes(9) No(1)
• 3 5 8 13 22 A
  2 3 5 9 B
  1 2 4 C
  here diff of 5-3=2
  8-5=3
  13-8=5
  22-13=9 so 2 3 5 9 is writn in next step
  next
  diff of 2-3=1
  5-3=2
  9-5=4 so 1 2 4 is writn in next step
  so 1 2 4 is a sequence multipled by 2
  so next number is 1 2 4 8
  c=8
  so B=9+8=17
  so A=22+17=39
  ANS= 39
  
  
• 12 years agoHelpfull: Yes(6) No(2)
• (3+8-1)/2=5
  (5+13-2)/2=8
  (8+22-4)/2=13
  (13+x-9)/2=22
  x=40
• 12 years agoHelpfull: Yes(4) No(8)
• well its kind of easy one.
  just see the total numbers missing between the given numbers in sequence... they are multiples of 2
  for eg. between 5 and 8 --6 and 7 are missing..i.e. 2 numbers are missing
  between 13 and 8 --9,10,11,12 are missing..i.e.4 numbers are missing and so on.
  thus after 22 comes 39 so that 16 numbers are missed. :)
• 12 years agoHelpfull: Yes(4) No(3)