CrazyEngineers Archive
Old, but evergreen and popular discussions on CrazyEngineers, presented to you in read-only mode.
@Kaustubh Katdare • 03 Dec, 2013 • 1 like
Found this puzzle on LinkedIn and I think it's a good mental exercise. Not at all difficult to crack, but should give you a good 30 seconds 😀

  • 9 = 90
  • 8 = 72
  • 7 = 56
  • 6 = 42
  • 3 = ??
If you take more than 30 seconds to crack this, you've gotta be needing some brain exercise. Spend time on CE and keep your brain engaged!
@Igneta D'Souza • 03 Dec, 2013 12😉
@Ankita Katdare • 03 Dec, 2013 18 it should be. Or is this a problem that has multiple correct answers based on assumptions or not-enough-data.
@Manashree Thokal • 03 Dec, 2013 12
@Anoop Kumar • 03 Dec, 2013 12 😀
x = x*(x+1)
@KSS Manian • 03 Dec, 2013 5 = 30
4 = 20.
3 = 12.
2 = 6.
1 = 2.

(or)

6 = 42
3 = 18 Which one is right???
@Sandeep Taurean • 06 Dec, 2013 12
@Shailaja Tiwari • 07 Dec, 2013
Kaustubh Katdare
😀

  • 9 = 90
  • 8 = 72
  • 7 = 56
  • 6 = 42
  • 3 = ??
time taken<20sec
ans: 12
@Aadit Kapoor • 07 Dec, 2013 ans : 18 (time taken 9 seconds)

explanation-:

9 = 90
8 * 9 = 72
7 * 8 = 56
6 * 7 = 42
3 * 6 = 18
@Sanyam Khurana • 07 Dec, 2013 12..

Took like just 2 sec 😛
@Anoop Kumar • 07 Dec, 2013 What is logic for getting 18?
@Shailaja Tiwari • 08 Dec, 2013
ianoop
What is logic for getting 18?
they must have done by this way :
  • 9 = 90
  • (8*9=72)
  • 8 = 72
  • ( 7*8=56)
  • 7 = 56
  • (6*7=42)
  • 6 = 42
  • (3*6=18)
  • 3 = ??
@Anoop Kumar • 08 Dec, 2013
Shailaja Tiwari
they must have done by this way :
  • 9 = 90
  • (8*9=72)
  • 8 = 72
  • ( 7*8=56)
  • 7 = 56
  • (6*7=42)
  • 6 = 42
  • (3*6=18)
  • 3 = ??
Really this is logic😨 , where did 9=90 came from☕ and why 3 came in series after 6, while other numbers are just x-1.

Why not x = x*(x+1).
@Shailaja Tiwari • 09 Dec, 2013 9=90 - as 8 is multiplied with its higher consecutive no. 9,similarly they must have added 9 with its higher consecutive no.10.
and don't know about the series problem ,others may not have noticed it
@Shailaja Tiwari • 09 Dec, 2013 anyway what's the right answer/
😨
@Ajay Pandey • 09 Dec, 2013 Right answer is 18 or 12 depends on ur logic.In objective exams, options must be either 12 or 18 not both.My answer is 12 bcos first match a pattern and then relation between consecutive options.
@Anoop Kumar • 09 Dec, 2013
Ajay Pandey
Right answer is 18 or 12 depends on ur logic.In objective exams, options must be either 12 or 18 not both.My answer is 12 bcos first match a pattern and then relation between consecutive options.
Still not convinced, how some of us getting 18.
@Ajay Pandey • 09 Dec, 2013 8*9=72
7*8=56
6*7=42
3*6=18
by wrong logic ......😀 right answer is 12
@sargam shukla • 09 Dec, 2013
Kaustubh Katdare
Found this puzzle on LinkedIn and I think it's a good mental exercise. Not at all difficult to crack, but should give you a good 30 seconds 😀

  • 9 = 90
  • 8 = 72
  • 7 = 56
  • 6 = 42
  • 3 = ??
If you take more than 30 seconds to crack this, you've gotta be needing some brain exercise. Spend time on CE and keep your brain engaged!
12
@Aadit Kapoor • 11 Dec, 2013 write a program to print a message without using printf function.
@Raj A • 14 Dec, 2013 12
@Sarathkumar Chandrasekaran • 14 Dec, 2013 12
@madhu27 • 18 Dec, 2013 12 or 18 based on our assumption....
But i think 12 suits the most....
Took <15 s.....
@jeshukb09 • 28 Dec, 2013 18
@yogi.bharadwaj • 28 Dec, 2013
Kaustubh Katdare
Found this puzzle on LinkedIn and I think it's a good mental exercise. Not at all difficult to crack, but should give you a good 30 seconds 😀

  • 9 = 90
  • 8 = 72
  • 7 = 56
  • 6 = 42
  • 3 = ??
If you take more than 30 seconds to crack this, you've gotta be needing some brain exercise. Spend time on CE and keep your brain engaged!
it should be 12
@vijay jangid • 05 Jan, 2014 12
@Karthikeyan jaisankar • 07 Jan, 2014 18🎉
@KenJackson • 07 Jan, 2014 • 1 like
Aadit Kapoor
write a program to print a message without using printf function.
At first I thought you must have posted in the wrong thread. But now I think I see that you think the answer 18 is bad logic, a non sequitur, so you posted your own non sequitur to protest. Right?

BTW. The answer to your puzzle is trivial if using one of the many computer languages that don't have a printf function.
@pavani kumari • 31 Aug, 2014
Kaustubh Katdare
Found this puzzle on LinkedIn and I think it's a good mental exercise. Not at all difficult to crack, but should give you a good 30 seconds 😀

  • 9 = 90
  • 8 = 72
  • 7 = 56
  • 6 = 42
  • 3 = ??
If you take more than 30 seconds to crack this, you've gotta be needing some brain exercise. Spend time on CE and keep your brain engaged!
its 18
@Shashank Moghe • 12 Sep, 2014 Well 18 (3-4 seconds). Also, if you (want to) intrapolate the series, the answer comes to 12. There seems to be a confusion as to which one is correct.

If it were up to me , I would justify 18 as the correct answer because of the way the question is presented. I was not "told to" intrapolate.
@Karthikeyan jaisankar • 13 Sep, 2014 18!!! 😀
@ManojKiran Eda • 19 Sep, 2014 12
@Satheesh S.S • 06 May, 2015 a*(a+1) so 12
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