This math trick can help you multiply any two-digit number by 11.
In one video, Resendiz stitched a TikTok of @zhcyt’s girlfriend @munchie.michelle quickly solving a multiplication problem. He asked @munchie.michelle what 11 multiplied by 32 is while she was driving. She quickly responded with the correct answer: 352.
Resendiz assumed @munchie.michelle was using this handy math trick.
“She used the 11s trick by multiplying the other number by 10 and adding another group to itself, giving you 352. It works every time,” Resendiz said.
The math tutor then wrote out the equation on a whiteboard. First, she multiplied 32 by 10 to get 320. Then she added the original number, 32, to 320 to arrive at 352.
“Why didn’t teachers show us this?” a person commented.
“That’s what I do in school all the time,” another said.
“That’s insane,” someone wrote.
Resendiz’s method isn’t the only one that works, however. You can add the two digits of the number being multiplied by 11 and place the answer in between the original number. So in the same equation, you would simply add three and two to get five then place five between three and two to arrive at 352.
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