Combining word search with a crossword puzzle and using numbers instead of letters, you get Number Search, with homemade clues made from randomly generated grids of numbers. Try your luck with the sample here.
| 2 | 8 | 8 | 6 | 6 | 6 | 6 |
| 1 | 9 | 9 | 1 | 3 | 6 | 4 |
| 5 | 8 | 2 | 2 | 1 | 7 | 2 |
| 4 | 3 | 2 | 2 | 5 | 4 | 8 |
| 8 | 6 | 8 | 1 | 0 | 6 | 8 |
| 4 | 2 | 0 | 6 | 0 | 7 | 9 |
| 5 | 7 | 7 | 5 | 9 | 8 | 7 |
The dice game called Take Sides is a clever variation on target games. The goal of the game is to design an equation using only the numbers on all 5 dice (once each), using arithmetic operators (including exponents) and concatenation.
Let’s take an example roll as follows.
\[2, 2, 3, 3, 5\]
Here are two solutions (there are more):
Try it yourself! For fun, try different amounts of dice and see if it’s easier or harder. See this article on Take Sides for more.
These are logic puzzles that include math. You solve them by using either addition or multiplication (indicated with the lower right symbol) to get entries that add or multiply to the numbers at the end of the row or column. Usually there are limitations written below the puzzle. It’s fun to generate these puzzles by reverse engineering them.
Here’s an example. If you set \(a\)–\(i\) to small integers, you can solve for \(u\)–\(z\), reveal these as the “answers”, and ask the world to solve for \(a\)–\(i\), a Yohaku puzzle.
| \(\dfrac{1}{a}\) | \(\dfrac{1}{b}\) | \(\dfrac{1}{c}\) | \(u\) |
| \(\dfrac{1}{d}\) | \(\dfrac{1}{e}\) | \(\dfrac{1}{f}\) | \(v\) |
| \(\dfrac{1}{g}\) | \(\dfrac{1}{h}\) | \(\dfrac{1}{i}\) | \(w\) |
| \(x\) | \(y\) | \(z\) | \(\times\) |
| \(a = 4\) | \(b = 5\) | \(c = 10\) | \(d = 8\) |
| \(e = 2\) | \(f = 12\) | \(g = 7\) | \(h = 3\) |
| \(i = 11\) |
| \(u = \dfrac{11}{20}\) | \(v = \dfrac{17}{24}\) | \(w = \dfrac{131}{231}\) |
| \(x = \dfrac{11}{24}\) | \(y = \dfrac{31}{30}\) | \(z = \dfrac{181}{660}\) |
Can you come up with your own Yohaku puzzle this way? See Mike Jacobs’ Yohaku site at https://www.yohaku.ca for more on this type of puzzle.
Each letter in the given words needs to be substituted with a digit from 0–9 uniquely such that the phrase is correct arithmetically. There is usually only one solution, but it is not guaranteed.
Here are some we have tried:
Give them a try! For more, see Mike Keith’s fantastic site at http://www.cadaeic.net/alphas.htm.
Can you arrange the numerals 1 to 9 in a single fraction that equals exactly \(\dfrac{1}{3}\)? Can you solve this for all the unit fractions with a denominator from 2 to 19? Can you spot a pattern? Can we name the fractions that have no corresponding answers to this puzzle (\(\dfrac{1}{10}\) and \(\dfrac{1}{11}\)) a certain kind of number? How about the unit fractions that have unique solutions, like \(\dfrac{1}{18}\)?