Note: we have adjusted this story since it was first published, as our math was slightly off initially. We apologize for any confusion.

When Halo 3's first day sales tally came in Microsoft proudly trumpeted that the game racked in $170 million. What they didn't tell us, however, was exactly how many copies of the game were sold, nor did they provide a breakdown between the standard, limited and legendary editions.

Well, GameDaily BIZ likes numbers and we weren't satisfied with having nothing but a dollar total. We got in touch with one of our corporate contacts at a major retailer who told us that generally for every four standard copies sold, two limited edition copies and one legendary edition is sold. If that breakdown can be applied nationally for all outlets selling Halo 3, some simple math can yield a day one total unit amount, which can then be broken down by the provided ratios to give us unit amounts for each of the three SKUs.

The breakdown suggests that 14 percent of copies were legendary, 29 percent were limited edition, and 57 percent were standard edition. Therefore, the following equation can be solved for T (where T = total units).

(0.14T x $129.99) + (0.29T X $69.99) + (0.57T x $59.99) = $170,000,000

Solving the above shows that T = 2.34 million units.

Now that we have total units we can apply the ratios to give us a breakdown as follows:

• Standard edition: 1,333,800 units
• Limited edition (aka 'scratched discs edition'): 678,600 units
• Legendary edition: 327,600 units

The grand total of 2.34 million units sold on the first day is significantly higher than the 1.7 million copies that Microsoft said were pre-ordered, meaning that nearly another 700,000 people bought the game without any pre-order. By our estimates then, Halo 3 fell just short of meeting Halo 2's total of 2.4 million copies sold in the first 24 hours.

In addition, with all the hype around Halo 3, the game technically might not even have sold out. Our source indicated that his company still has stock from the initial allotment, and he reminded us that Microsoft's numbers are typically sell-in, not sell-through.

A Goldman Sachs analyst previously predicted that 4.2 million copies of Halo 3 would ship during the first week.