I am thinking of a 5 digit number that when tripled is a perfect square.

Also, when the 5 digit number is split, the first number is double the second one. What is the five digit number?

(Splitting the 5 digit number into two numbers means 12345 into 1 and 2345 or 123 and 45.)

This one is easy with a spreadsheet application. The "split" thing tells you that the last two numbers are from 50 to 99, and the first two are double the last. When you do that and concatenate the numbers then triple and squareroot, the number just pops out at you. Your number is 13467, when tripled is 40401, the squareroot of which is 201.

Posted by Lawrence on 2003-08-24 11:35:15