If you multiply me by myself, add 12, divide by 4, and then subtract 5, you get the exact number you started with. What number am I?
6
Let the number be x. Equation: ((x * x + 12) / 4) - 5 = x. For x = 6: (36 + 12)/4 - 5 = 48/4 - 5 = 12 - 5 = 7? Wait, let's check: 6*6=36, 36+12=48, 48/4=12, 12-5=7. Let's try 4: 16+12=28, 28/4=7, 7-5=2 (no). Let's solve x^2 + 12 = 4x + 20 => x^2 - 4x - 8 = 0... wait. Let's make an easier one. Try 2: 2*2=4, 4+12=16, 16/4=4, 4-5=-1 (no). Let's use a simpler riddle.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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