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Logical Puzzles Hard 3 min

A code consists of three different digits. The first digit is twice the second. The third digit is one more than the second. If the sum of the digits is 10, what is the code?

Hint
Let the second digit be x.

Answer

436.

Explanation

Let the second digit be x. The first is 2x and the third is x+1. Therefore 2x+x+x+1=10, giving x=2.25, so the stated conditions have no integer-digit solution.

Step-by-Step Solution

2x + x + (x+1) = 10.
4x + 1 = 10.
x = 9/4.
Since a digit must be an integer, there is no valid code.
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