In a grid of numbers, each row sums to 30. Row 1 has 10, 12, and 8. Row 2 has 15, 5, and X. What is the value of X?
10
The sum of the numbers in Row 2 must equal 30. 15 + 5 + X = 30. 20 + X = 30, so X = 10.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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