Find the next number: 12,12,18,45,180,1170,?

Replies

• 

  bayazidahmed

  12285
  
  Shall I give the solution or wait for some one else to rattle their brain and figure it out?
• 

  Kaustubh Katdare

  bayazidahmed

  12285
  
  Shall I give the solution or wait for some one else to rattle their brain and figure it out?

  😁 Wait!
  
  If no one replies in next 24 hours, post the explanation!
• 

  bayazidahmed

  I am too busy to post the explanation now. I'll leave it for another 24 hours.
• 

  mahul

  Yep, my answer matches with that of bayazidahmed, 12285.
  
  Here's the solution:
  
  Lets name the general term of the sequence T(n)
  
  The sequence (say R(n)) where R(n)=T(n+1)/T(n)
  is 1,1.5,2.5,4,6.5...
  
  The sequnece (say S(n)) where S(n)=R(n+1)-R(n)
  is 0.5,1,1.5,2.5....
  
  
  Thus S(n) can be thought of a fibonacci style sequence where S(n)=S(n-1)+S(n-2)
  Considering this relation, the next term in S(n) would be 1.5+2.5=4
  
  Considering this, the next trem in R(n) would be 6.5+4=10.5
  
  Thus the next term in T(n)=1170*10.5 = 12285