Art of Problem Solving

AoPS Online

2007 AMC 8 Problems/Problem 18

Revision as of 02:59, 14 November 2010 by Thealexrider (talk | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

When you multiply $303$ by $505$ , it's $153015$ . The ones digit plus thousands digit is $5$ $+$ $3$ $=$ $8$ . $30303$ $\times$ $50505$ $=$ $1530453015$ . Note that the ones and thousands digits are, added together, $8$ . (and so on...) So the answer is $\boxed{D}$ $(8)$ .

Retrieved from "https://artofproblemsolving.com/wiki/index.php?title=2007_AMC_8_Problems/Problem_18&oldid=36036"

© 2024 AoPS Incorporated