Despite his billions, President Trump still enjoys a $22 McDonald's dinner

These billionaires have all the money in the world—and they still eat at...

President Donald Trump has an estimated net worth of more than $3 billion as well as access to world-class chefs at the White House. And still, his go-to dinner is a $22 meal from McDonald's.

That's according to forthcoming book "Let Trump Be Trump," co-written by former campaign manager Corey Lewandowski and former campaign aide David Bossie. The book chronicles then-presidential candidate Trump's journey leading up to the 2016 election.

"Trump's appetite seems to know no bounds when it comes to McDonald's," the authors write in an excerpt of the book pre-published in The Washington Post. A typical dinner order consisted of "two Big Macs, two Fillet-O-Fish and a chocolate malted [shake]."

According to the McDonald's mobile-ordering app, those menu items add up to an estimated $22.15, depending on the size of the shake.

Warren Buffett keeps his breakfast under $3.17

That price doesn't include deals or promotions, though. The app, citing McDonald's "McPick 2 for $5.00" deal, automatically reduced the subtotal to $12.99 and the grand total, including sales tax, to $14.29.

The two Big Macs, individually priced at $4.79 and at $9.58 for two, were reduced to $5.00 for the pair. The Fillet-O-Fish sandwiches saw the same shift. A medium chocolate shake, priced at $2.99, stayed the same. A small shake would cost $2.00 and a large would cost $3.09.

Menu prices also vary slightly based on region.

How to eat on just $3 a day

The president isn't the only wealthy person who nonetheless opts for fast food. Investing legend and chief executive officer of Berkshire Hathaway Warren Buffett says in the HBO documentary "Becoming Warren Buffett" that he eats breakfast at McDonald's daily. But he never spends more than $3.17.

"I tell my wife, as I shave in the morning … either $2.61, $2.95 or $3.17," he says. "And she puts that amount in the cup by me here [in the car]. When I'm not feeling quite so prosperous, I might go with the $2.61, which is two sausage patties. I put them together and pour myself a Coke."

Bill Gates, co-founder of Microsoft and Buffett's longtime friend, is a fast-food aficionado, too. In fact, he owns a rare McGold card, which gets him free meals anywhere in the world.

And Facebook co-founder and chief executive officer Mark Zuckerberg is similarly loyal to the brand. During his 2012 honeymoon with wife Priscilla Chan, he was spotted eating McDonald's near the Piazza di Spagna in Rome.

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