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A Book Puzzle
A simple math riddle
This math challenge requires no formal mathematical training to solve. See if you can figure it out!
A book costs $1 plus a third of its price. How much does it cost?
The solution is below. Take your time to solve this one! If you peek early, you hurt no one but yourself. Once you look, the problem is gone forever.
If you’re stuck, try writing it out as an equation. That’s what I had to do to get this one.
An equation really helps here. Represent the price of the book with x. We can now rewrite the problem statement as follows.
Rearranging this equation to solve for x.
We have calculated that the book costs $1.50! The strange way of describing the price became simple once it was written in mathematical form.
This problem was inspired by a similar puzzle from the book The Moscow Puzzles. It’s a fantastic source of puzzles like this one.
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