Can You Solve This Viral Addition Problem?

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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.


The answer to this brainteaser is 96. Watch the video to learn how to arrive at that answer.

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?

Share the knowledge!

Key Facts In This Video

  1. Here is the find the heavy ball logic puzzle: 00:01

  2. Here is the solution to the find the heavy ball logic puzzle: 02:55

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