Solution to Puzzle #11: The 10-digit number

I got the most number of correct answers for this puzzle. I was particularly impressed by Ameya Kulkarni (from London), Salil Kuchlous (from Bangalore) and Tishya Chaudhry and Anisha Sharma Goyal (both Gurgaon) – all kids who solved the puzzle.

The puzzle had appeared originally in MIT’s Technology Review, which was written by Allan J. Gottlieb, and the solution appeared in the February 1968 issue. The solution is more a trial and error process, with a few rules applied to it. I have recorded the solution as always. If anyone would like to have a more complete proof, I am happy to send it to them – please write to me directly at alokgoyal_2001@yahoo.com.

The correct answer is 6,210,001,000. This is a unique answer for 10 digits. For fewer than 10 digits, the answers are 1210, 2020, 21200, 3211000, 42101000, 521001000.

http://www.educreations.com/lesson/view/solution-to-puzzle-11/6872861/?s=kxaDOF&ref=link

Thanks for trying the puzzle!

 

This entry was posted in Puzzles and tagged , , . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s