Mystery product

18th February 2005 at 00:00
ABCDE is a five-digit integer. Each digit is different.

A six-digit integer X is formed by putting a 1 at the right-hand end of ABCDE.

Another six-digit integer Y is formed by putting a 1 at the left-hand end of ABCDE.

X is three times Y.


What is the five-digit integer ABCDE?

SOLUTIONS Fish tank (age 6 to 10) Mystery product (age 10 to 14) ABCDE is 42 857.

Log-in as an existing print or digital subscriber

Forgotten your subscriber ID?


To access this content and the full TES archive, subscribe now.

View subscriber offers


Get TES online and delivered to your door – for less than the price of a coffee

Save 33% off the cover price with this great subscription offer. Every copy delivered to your door by first-class post, plus full access to TES online and the TES app for just £1.90 per week.
Subscribers also enjoy a range of fantastic offers and benefits worth over £270:

  • Discounts off TES Institute courses
  • Access over 200,000 articles in the TES online archive
  • Free Tastecard membership worth £79.99
  • Discounts with Zipcar,, Virgin Wines and other partners
Order your low-cost subscription today