2 October
2026
1 October
2026
Another interesting puzzle
28 September
2026
Monday morning math puzzle
Well, I struggled with this one over the weekend. Finally, early this morning, it struck me.
In twelfth grade, I used to look forward to these problems. Now, I just lose sleep over the weekend 🙁
Times have changed, for sure!!
There are 8 identical balls and 4 colored boxes. You can put any number of balls in any of the boxes – including none. How many different ways can you do it?
7 July
2026
I am finally hanging up my boots with this game
Many moons back, my friend Mita Basu had introduced me to this game – travle.earth. The whole idea is to travel from Country A to Country B by crossing only land borders. There are some quirks in the game – It thinks of Siachen Glacier as a country, it does not think you can cross from Morocco to Western Sahara by land, and for some reason, it will not let me go from Poland to Russia directly, although I have been to their land border myself (exclave of Kaliningrad).
But I have now reached the 1000 game mark without failing once. And I am ready to move on to my next geography game. First, I have to dig through my messages from Mita. About a month ago, she sent me another game that I haven’t opened yet!
If you want to learn about country boundaries, this is a great game to try.
28 June
2026
Sunday morning puzzle
Which of the following statements – if any – is/are true? How do you logically work it out?
1. Exactly one statement in this list is false.
2. Exactly two statements in this list are false.
3. Exactly three statements in this list are false.
4. Exactly four statements in this list are false.
5 Exactly five statements in this list are false.
6. Exactly six statements in this list are false.
7. Exactly seven statements in this list are false.
8. Exactly eight statements in this list are false.
9. Exactly nine statements in this list are false.
10. Exactly ten statements in this list are false.
19 May
2026
Map quiz after some time
6 October
2025
What does “SOS” stand for?
Here is one of the interesting things I learned while picking up Morse code. I can’t believe I have lived all my life without realizing this.
What does the term “SOS” stand for? Growing up, I always thought that it stood for “Save Our Souls”. I believe I first heard this while reading about the story of the Titanic. Some think of it as “Save Our Ship”.
It turns out that “SOS” is not an abbreviation at all. About 75 years after Morse code was created, around the start of the 1900s, the Germans helped set a universal distress code: SOS. They chose it because its Morse pattern [… — …] was easy to recognize. Before SOS, other distress signals were used, with “CQD” being the most common.
So, SOS does not stand for any English phrase. And even if it did stand for something, it would have been very likely a German phrase!
Did you know that?
24 August
2025
A quick geometry problem
22 August
2025
Why is my math not matching with ChatGPT?
I was driving back from the airport when I got a call from my old buddy SK and his son. Apparently, they were stuck on a math problem. What I understood is this:
SK’s son and his friend are trying to get two tickets to a concert. (He told me the name of the concert but of course, that was all Greek to me). The organizers are opening 50,000 slots you can apply to. And they will pick 4,500 of them as winners. In other words, there are only 4,500 seats available.
SK’s son and his friend bought 25 slots.
Question was what is the probability that the two friends would be able to go to the concert?
Apparently ChatGPT was saying 90%. SK’s intuition was far lower than that. His son felt that it made sense. So, over the phone we worked out the approach and agreed it will be a high number.
I got a message yesterday from SK that his son and his friend are indeed going to the show!
This early morning, curiosity got the better of me and I sat down with paper and pen to figure out what the probability would be.
Now, I am stumped! My answer is very different from what SK and his son reported as ChatGPT’s response was.
What do you think is the probability?
Answer published here
18 August
2025
Triangle and 9 digits puzzle
This puzzle comes from my good friend Amrith.
Fill the three vertices and two spots on each side of the triangle with the numbers 1 thru 9 (using each only once) such that each side adds up to 20.
Multiple solutions are possible.
What approach did you use (other than simple trial and error)?
Answer posted here: https://www.rajibroy.com/2025/08/22/answer-to-triangle-and-9-digits/
