Value of N puzzle


The integers from 1 to N are written down in alphabetical order in English. ‘Two thousand and eleven’ is in position 2011. What is N ?

Reveal Solution
If N = 2011 then 2011 is only nine from the end. So we need to continue until exactly nine more numbers slot in before 2011. These will be 2018, 2080 to 2087. So N is 2087.
Problem Page Coordinator: Stephen Lee CMath MIMA – Mathematics in Education and Industry
Acknowledgement: The IMA are indebted to MEI for sourcing and supplying Mathematics Today with these well-known puzzles.
First published in Mathematics Today (December 2014)
Published