All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars
 perplexus dot info

 The Last Three Digits (Posted on 2007-08-28)
A number and its square both have the same last three digits. What are the possibilities for those digits?

 See The Solution Submitted by Brian Smith Rating: 4.0000 (3 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
 yes, full list | Comment 2 of 8 |
(In reply to Solution (not necessarily a full list) by Guest)

000
001
376
625

is indeed the full list, found by

FOR i = 0 TO 999
sq = i * i
d\$ = "000" + LTRIM\$(STR\$(sq))
n = VAL(RIGHT\$(d\$, 3))
IF i = n THEN PRINT RIGHT\$(d\$, 3)
NEXT

That digits further to the left than the hundreds position could interfere is not a possibility, as one could consider the numbers in base 1000. When squaring a number in any base system, or any multiplication in any base system, multiplying the rightmost digits always results in the rightmost digit of the answer, including base-1000.

 Posted by Charlie on 2007-08-28 15:12:04

 Search: Search body:
Forums (1)