A&W Restaurants is releasing a cleverly rebranded 1⁄3 lb. burger to make amends for a decades-old marketing mishap that’s seen renewed interest on social media lately. Just check out this Instagram post.

In the 1980s, A&W tried to compete with the immensely popular McDonald’s Quarter Pounder by offering a bigger, juicier 1⁄3 Pound Burger at the same price. Unfortunately, Americans aren’t so great at math. Confused consumers wrongly assumed that 1⁄4 was bigger than 1⁄3 and the whole experiment went down in history as a huge marketing fail.

The chain—founded in 1919 and the oldest in America—has spent every waking moment since this embarrassing fiasco crunching the numbers, employing a team of top mathematicians and the creative services of ad agency CORNETT in an attempt to bounce back with a burger so big and a message so clear that no one in their right mind would think it’s smaller than a puny Quarter Pounder.

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Forget everything you know about fractions and wrap your mind around the whopping A&W 3/9 lb. Burger.

A&W is launching the 3/9 lb. Burger with a dramatic reenactment of the “Eureka!” moment. That video (see above), featuring mascot and math prodigy Rooty the Great Root Bear solving the unsolvable equation in his study, is the centerpiece of a paid media campaign that will run throughout the promotion

In addition, a number of creative assets like window clings, table tents, branded memes and GIFs were created for the promotion.

Fans of big burgers and big digits are encouraged to grab an A&W 3/9 lb. Burger from any of A&W’s 525 US locations while supplies last. If sold out, a 2/6 lb. Burger can be specially made at no extra charge.

“This story has been circulating for years,” says Liz Bazner, Director of Marketing at A&W, “and every few months it seems to gain momentum and reappear on social media. We’ve gotten tons of questions about it, but prior to now we haven’t been proactive about setting the record straight. We’re excited to have found a way to finally let America know that our burgers really are bigger and really are better.”

Marketing & Promotions, News, A&W