Treebeard's Stumper 17 December 1999

Millennium Magic

I think of the Y2K New Year as an odometer day, when digits reset to zero. It's just a number thing, so here's another. Circle any number on the grid below, and then cross out all the other numbers in its row and column. Now circle any remaining number and cross out all the others in its row and column. Do it again, and again, and then circle that last remaining number. The sum of your five circled numbers will always be 1,999! Can you make your own magic grid that adds up to 2000 for the new year? How does this work? How many solutions are there?

296	456	319	287	324
452	612	475	443	480
313	473	336	304	341
420	580	443	411	448
316	476	339	307	344

When you're done the grid might look like this,
though you'll probably select different numbers:

420 + 473 + 475 + 307 + 324 = 1,999

Answer

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