Host Alex Trebek on the set of Jeopardy.

AP

You take trivia answers that call for rapid-fire questions. You take a jumbo roulette wheel and the letters of the alphabet. What you’ve got are Jeopardy! and Wheel of Fortune, TV’s reigning syndicated shows for a quarter-century.

But that’s only for starters. Wheel has rallied 4.6 million of its daily 10.4 million viewers for the online Wheel Watchers Club, which gives members a crack at winning a prize from each day’s telecast. There are versions of both Wheel and Jeopardy! for personal computers, with Jeopardy! available on the PlayStation online network. And you can play variations of both shows on your cell phone.

What’s next? Come January, any cell phone owner can compete in real time against the daily trio of on-air Jeopardy! contestants (as well as against others from the audience of 9.5 million) while viewing the broadcast.

“Wheel and Jeopardy! have now transcended what we traditionally call programming,” says Harry Friedman, executive producer of both shows. “They are now a part of people’s lifestyle.”

One key to their success: Neither show has a habit of calling attention to itself, with the notable exception of software engineer Ken Jennings’ 74-game winning streak on Jeopardy in 2004, which not only made headlines and thrilled the public, but also threatened the steady-as-she-goes reliability that makes both shows so comfortable to watch.

Even if you haven’t tuned in since the Reagan administration (Jeopardy! is now celebrating its 25th season; Wheel premiered in syndication a year earlier, in 1983), you’re prepared for what you’ll see if you watch any day this week (check local listings).

Not that there haven’t been changes. Upgrading to high-definition television. Going on the road with more frequency and extravagance. Specially themed tournaments. Modifying the rules to energize the shows.

But Friedman speaks as the keeper of a sacred trust when he cites “our philosophy of not messing with the fundamental formats.”

“We keep the game the same,” he explains from his Los Angeles headquarters, “but we know we can change the show around it.”

He marvels at the shows’ compatibility. In most of their 200-plus markets, they air back-to-back, each having long ago proved itself as the ideal complement to the other.

“Wheel is a game, Jeopardy! is a quiz, and each of them requires its own skill set,” Friedman says. “Wheel is best played by people who are avid readers and who like to do crossword puzzles, because they understand what words look like, how they appear to the eye.

“That requires a different skill than playing a game that’s knowledge-based, like Jeopardy! But as they carry on in TV tandem, each show has struck out for other media platforms.”

In a few weeks, Jeopardy! will try to stake a claim in the high-tech frontier of TV interactivity. The newly introduced Jeopardy!Live will enable your cell phone to synch with Jeopardy! as it is telecast by your local TV station.

“For that one half-hour a night, the same questions that are being asked on TV will show up on your cell phone,” explains Eric Berger, Sony Pictures Television’s head of digital networks and mobile entertainment.

The phone will list three choices for the correct response. You must make your move faster than the on-air contestants.

Meanwhile, you’ll have the option of playing against other viewers by creating a buddy list. During each commercial break, your phone will display how you rank in the community you formed.

The cost for Jeopardy!Live will range between a monthly low of $2.99 and a purchase price maxing out at $7.99. It will be available from all major service providers, Berger says, and operate on most models.