When this math problem was initially posted on Facebook, it included the claim that only one in 1,000 people could solve it. The problem goes like this: If 1 + 4 = 5, 2 + 5 = 12, and 3 + 6 = 21, what is 8 + 11 = ? According to Presh Talwalkar of the YouTube channel MindYourDecisions, most people think the answer is 40. But that's not correct. Watch the video below or scroll down to find the correct answer.
Can You Solve This Viral Math Puzzle?
Get an explanation of the solution.
Denise's Birthday Brainteaser
This one came from the National Institute of Education in Singapore.
Find The Heavy Ball
One of the eight balls is slightly heavier than the rest. How do you find it?
Written by Curiosity Staff September 12, 2016
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