Sean Rossman

USA TODAY

Lt. B.J. Gruber won't forget the phrase, "Please excuse my dear Aunt Sally."

Not after he mistakenly mislead a 10-year-old girl who sought math help from the Marion, Ohio Police Department last week.

The girl, 10-year-old Lena Draper, was stumped by her math homework, so she sent a message to the police department's Facebook page early Saturday morning. Gruber, who mans the police account, responded a few hours later.

"I need a little help with my homework," the girl wrote from her mother's Facebook profile.

"OK with what?" asked Gruber.

"Well I don't understand (8+29)x15," she said, forcing Gruber to reach back into his memory. But he answered, "Do the numbers in the parentheses first so in essence it would be 37 x 15."

He was right. But on the next one, he admits, he wished he would have remembered "Please excuse my dear Aunt Sally," or PEMDAS, a trick for remembering what takes precedent in math equations: Parentheses, exponents, multiplication and division, and addition and subtraction." He told the girl to add first before multiplying.

Gruber, who doesn't promise to be a math expert, jokes he deserves an "A for effort."

He said he's never received a message quite like Lena's. He responds to about five to eight messages each day.

Molly Draper, Lena's mother, said she didn't believe her daughter at first.

"She actually took a lot of pride in it and told me right away," Molly said. Molly wasn't surprised by the response, noting "I know (the police) always have a good community relationship."

Lena's request has gone viral, showing up on several national news outlets. Her mother says the girl's "a bit overwhelmed, but absolutely loving it."

"She has always been her own PR person," Molly Draper said. "I'm not surprised at all. She was making phone calls and making arrangements at a young age."

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