When Salar Abdul-Baki won one of the 20 weekly prizes in Microsoft's Xbox Live Plug-in & Win contest last week, he wasn't home free.

Like all winners who live in Canada, the 17-year-old resident of Mississauga, Ontario, had to answer a math question to claim his prize. The question – ostensibly a test of the winner's mathematical skills – was typical of today's Canadian product sweepstakes: Multiply 90 by 2, divide by 6 and multiply by 12. The answer? 360, as in Xbox 360.

"I was not surprised with the question being simple, although I did ask for help to make sure I would not lose out on the prize," Abdul-Baki said in an e-mail interview. "I mean, everyone could make mistakes."

Canadians are routinely required to answer such mild brain teasers before collecting the kinds of giveaway prizes doled out to Americans without so much as a 2-plus-2. From McDonald's hockey trading cards to AOL Canada's Virtual Investor game, winners find themselves forced to exercise some elementary-school-level skills.

Myths regarding the origin of the skill tests abound. Abdul-Baki believed the question to be a real-world captcha – a simple test designed to foil automated software bots from entering sweepstakes.

In reality, the test is a hack of Canada's legal code by the promotions business. Canadian anti-gambling law makes it illegal to sell chances to win a prize, so promoters always offer a free method of entering each contest, and task every winner with a skill-testing question. By doing the latter, they argue, the game is no longer one merely of chance but a contest requiring some skill.

In decades past, the tests of skill were designed to be interesting. Challenges approved by the courts include estimating the number of beans in a jar and calculating the time it takes for a barrel to float downriver. Not all tests have received a legal passing grade, however. Canadian courts have shot down skill tests consisting of shooting a turkey at 50 yards, or quickly peeling a potato, on the grounds that they're too easy.

But a 1984 court case validated a simple, four-part mathematical question as a test of skill. The test? Multiply 228 by 21; add to that 10,824; divide the answer by 12; and subtract 1,121.

The Canadian court's stamp of approval paired with the simple nature of the question has made the four-part mathematics problem the de facto standard among product promotion sweepstakes.

It's also a standard in decline. In the past 20 years, expectations have lowered for Canadian sweepstakes winners. Today, many questions, such as the one used in Microsoft Canada's Xbox sweepstakes, have only three operations, and the tests rarely use numbers with more than two digits. Some questions use only single-digit numbers and ask contest winners to divide by 1.

"You don't have to have any type of aptitude," said Michael Katz, the CEO of Education411.com, a site that offers information on Canadian schools and whose sister site UC411.com hosts scholarship giveaways. "It is simply a way around or way to work within the laws."

When Katz's company reps test winners, they frequently just make up the problem on the spot, he said. Making the questions as simple as possible is natural, because you want the customer to be happy.

"We make it easy – we want them to win," Katz said.

Kevin Weber, a gaming and advertising lawyer with Elkind & Lipton, says he always urges his clients to make the tests tougher, but not everyone listens. He doubts that the Canadian government will ever crack down on companies posing easy skill-testing questions.

"No one is going to charge Tim Horton's or McDonald's or General Motors with this sort of thing," Weber said. "It's part of the criminal code. A judge is not going to give someone six months for lax skill-testing questions."

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