April 1, 2024

Occasional Puzzles - 🔢 Breaking Even

Occasional Addendum - A Better Solution to 🍪 Cookie Conundrum!

Before we get into today's puzzle, we wanted to share an update on the hourglass puzzle. Reader Owen in Seattle wrote in with a more elegant solution that doesn't involve waiting at the beginning!

1. Flip both the seven-minute hourglass and the four-minute hourglass, then immediately put the cookies in the oven.
2. Four minutes later, when the four-minute hourglass is empty, flip it again.
3. When the seven-minute hourglass is empty, flip it again. At this point, seven minutes have passed, and the four-minute hourglass has one minute left.
4. One minute later, when the four-minute hourglass is empty, eight minutes have elapsed since you put the cookies in the oven. Now, flip the seven-minute hourglass. The seven-minute hourglass started one minute ago, meaning that if you flip it back over, it's now a one-minute timer!
5. When the seven-minute hourglass is empty, you're at exactly nine minutes and ready for cookies!

Thanks, Owen!

Today's Puzzle - 🔢 Breaking Even

Fill in the following 3x3 grid with the numbers 1-9 such that the sum of each row and the sum of each column is even. Each number can only be used once.

Source: Giphy

Previous Puzzle - 🐟 Fishy Fish

Puzzle

I have cities, but no houses.
I have mountains, but no trees.
I have water, but no fish.
What am I?

Solution [SPOILER]

A map!

PS, for those curious: On further investigation, it seems the riddle is at least 60 years old. A version of it appeared in an issue of Southern Folklore Quarterly in 1962. If you can find an earlier citation, we would be interested to know!