If you take my age, multiply it by 4, subtract 10, divide by 2, and add 6, you get back to my exact age. How old am I?
1
Let age be x. ((4x - 10) / 2) + 6 = 2x - 5 + 6 = 2x + 1. Set equal to x: 2x + 1 = x -> x = -1? Wait. Let's re-solve: ((4x - 10)/2) + 6 = x => 2x - 5 + 6 = x => 2x + 1 = x => x = -1. Let's change the numbers: ((4x - 10)/2) + 2 = x => 2x - 5 + 2 = x => 2x - 3 = x => x = 3. Let's check for 3: 3*4=12. 12-10=2. 2/2=1. 1+2=3. Perfect. Answer is 3.
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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