Playing the lottery can provide a thrill, and it's tempting to purchase a ticket or several when, like this week, the Powerball jackpot is a whopping $425 million. 

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But if you're trying to get ready to retire — or simply trying to make ends meet on a limited budget — you need to think hard about devoting precious financial resources to long-shot jackpot hopes.

Nearly one-half of boomers in the United States between the ages of 56 and 62 are at risk of not having enough income in retirement to pay for basic necessities and uninsured health costs, much less Powerball and Mega Millions tickets. And the likelihood of winning the grand prize in a state lottery can be as astronomical as 1 in 175 million, depending on the game, according to state lottery commissions.

Yet despite the poor odds, about 50 percent of people over 50 report some form of gambling including playing the lottery, according to Keith Whyte, executive director of the National Council on Problem Gambling.

When Gallup conducted a poll a few years back, it found that two out of three Americans had gambled during the previous 12 months. The most popular form of gambling was the state lottery: 49 percent of those polled had bought tickets. The age group with the highest rate of gambling (69 percent) was 50- to 64-year-olds. Sixty-one percent of the people polled who were 65 and up had gambled in some form during the prior year.

Spending a dollar a week to play your lucky numbers won't break the bank; just don't count on winnings to fund your retirement. The keys are playing the lottery for fun and spending within your means.

"You need to know how to gamble responsibly," says Whyte, "which means knowing the odds, being able to set a limit of time and money, and being able to stick to it."

Here are three lottery rules to live by:

1. Play for fun

Truth be told, most people who play the lottery are hoping to win big. Maybe the dream is to buy a new home, put the grandkids through college, or simply quit work and live the good life. In reality, almost no one hits the jackpot. Assume you won't either.

"The fact is the chance of winning millions in any state lottery is almost as good if you have a ticket or don't have a ticket, " says Arnie Wexler, co-founder of Arnie & Sheila Wexler Associates, which provides counseling for gambling problems.

If you play the lottery, play it for entertainment only, says Wexler. Don't play to get out of debt or provide for your future. The lottery is no substitute for a steady job and solid retirement planning.

Next: Set limits — and stick to them. »