CrazyEngineers Archive

Old, but evergreen and popular discussions on CrazyEngineers, presented to you in read-only mode.

@Kaustubh Katdare • 04 Aug, 2008

The series is -

12,12,18,45,180,1170,?

What's the next number in above series?

12,12,18,45,180,1170,?

What's the next number in above series?

@bayazidahmed • 07 Aug, 2008
12285

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

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

@Kaustubh Katdare • 07 Aug, 2008

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

😁 Wait!bayazidahmed12285

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

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

@bayazidahmed • 09 Aug, 2008
I am too busy to post the explanation now. I'll leave it for another 24 hours.

@mahul • 09 Aug, 2008
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 =

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**
5.4k views

## Related Posts

@Kaustubh Katdare · Apr 28, 2014

We run a single box setup with PHP 5.4 and considering whether we should upgrade to PHP 5.5 to utilise the built in Zend Optimiser+. There's no clear comparison available...

2.1k views

@Radhika Deshpande · Oct 12, 2011

The following are the Questions and Answers that mostly the Ambassador asked in the Embassy during the interview. So you must prepare yourself about all these questions before going for...

2k views

@saimriyaz · Jun 17, 2011

I just want to know that in which case i will get good salary package?
Case 1. I did M Tech. from IIT and I m a fresher and got...

5k views

@arnab.aeroman · May 16, 2011

I have just completed my second year for aeronautical engg. any one can tell me a place where i can do inplant training related to my field. plz give contact...

1.9k views

@Kaustubh Katdare · Sep 14, 2015

Just created a whatsapp image that you can share with your friends and fellow engineers. Instead of just forward 'Happy Engineers Day', let's educate people about the reason.

2.9k views