This is another great and fun critical thinking puzzle to tease your brain and sharpen your basic math skills. This is for those who love math puzzles. Let’s challenge your brain!

## Challenge:

12 = 13

35 = 28

47 = 311

10 = ?

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The correct answer is 11.

To answer this question, we need to find the pattern. For these equations, don’t try to find a relationship between numbers on both sides. Instead, consider the digits of each number and try to find a relationship between the two digits of the number in the left side. What operation between the digits of the number in the left side can create the digits of the number of the ride side?

12 = 13 35 = 28 47 = 311 10 = ?

Find the difference of two digits of the number in the left side. That is the left digit of the number in the right side.

The digit (or digits) in the right side of the answer is created by adding the two digits of the first number. For example, 12 = 13

Difference of 2 and 1 is 1 and the sum of 1 and 2 is 3.

Therefore, the answer is 11.

1 – 0 = 1 and 1 + 0 = 1