Singer Chaeyeon’s infamously televised math mistake was used in a published research paper, according to the singer.

In her appearance on Monday's episode of the MBC talk show "Radio Star" (2007-), the singer revealed that British mathematician David Tall contacted her to ask for permission to feature her mistake in his paper, which was published in 2017.


The singer wrongfully answered that 2+2x2 is 8 during a game and was pushed to a swimming pool as punishment, which was broadcast in an episode of the SBS variety show “Explosion! Concentration" (2007).

“Tall asked if he could use the question for his paper after he accidentally discovered the video because he found the question to be pretty simple but also easy to get wrong,” Chaeyeon said.

“I initially hesitated but agreed, thinking it might help others who are also confused about these types of math formulas like me,” the singer continued. “Thanks to the professor, my public error is no longer a joke but a legitimate debate topic.”

Scenes from the TV show depicting her mistakes were introduced in Tall's paper, "Making sense of elementary arithmetic and algebra for long-term success" (2017).

"The experience of reading symbols sequentially from left to right makes it natural to first perform 2 + 2, then multiply the result 4 by 2," analyzed Tall in the paper. "The rule that multiplication is performed before addition involves calculating the expression in a less natural sequence."

Mathematically speaking, 2+2x2=8 is incorrect because the order of operations puts multiplication before addition. The correct answer is 6.

Chaeyeon made her debut in Korea as a singer in 2003 with her first studio album, "it's my time" (2003). She is known for her songs such as "Third Love" (2006), "Bazzaya" (2018) and "I Sometimes Shed Tears" (2021).

BY LEE JI-WON [lee.jiwon10@joongang.co.kr]