Lou Zerr is trying to pick up a woman at a bar. The woman, Denise, is reluctant to give out her number, but she gives Lou a clue.

"My sister, Elise and I have the same digits in our phone numbers, just in reverse order. Elise's number is also evenly divisible by mine."

What is Denise's phone number?

(Note: this IS NOT a real exchange, as far as I know. Assume the phone number has 10 digits: 7 digit number + 3 digit area code.)

(In reply to re(2): Another non-trivial solution by fwaff)

Am I missing something ? "Evenly" means "precisely". (I found this quote on a math website: "A number is evenly divisible by 3 if the sum of all its digits is evenly divisible by 3.")    

9801009108 / 1089001089 = 9  (evenly divisible by 1089001089)

9899999901 / 1099999989 = 9 (evenly divisible by 1099999989)

 

 

 

 

Edited on April 19, 2004, 11:21 am

Posted by Penny on 2004-04-19 10:38:54