Smart Puzzles I Came Across — Part 1
Can you solve them?
I did not create the following puzzles. They are ordered starting from the easiest to the toughest. Except with the first one, the only one among these I couldn’t solve, which in retrospect, is the easiest, I was very impressed with myself when I cracked them.
You walk into a hall where a party is happening. They are all strangers to you. You know something about the people though. They all are compulsively honest or compulsive liars. Your mission is to find the liars, all of them. What’s the least number of questions you need to ask around to find the truth and complete the mission? And what are those questions?
You’ve got 9 coins with you, and one of them is a fake one. The fake one weighs slightly less than the others which are all of equal weight. But the difference in weight is so small that you need a weighing scale to know the difference. And you got one like the one in the picture below.
You got no standard weights, just this weighing scale above, and the 9 coins. How do you find the fake one using the weighing scale only twice?
In a time before Google Maps, you are walking down a road when you reach a 3-way junction. Only one of the 2 roads ahead leads to your destination (Let’s say the destination is Kerala), and you don’t know which. There are 2 people by the road, one of whom, is a compulsive liar, and the other is compulsively truthful. They both know the road to Kerala. You don’t know who the liar is. You are allowed to ask one question to one of them only to figure out the right path. What would you ask?
4 friends meet up for a few drinks. They had Vodka in 11 glasses, the same amount in each glass. They start drinking. The 4 of them initially only knew that each of them had drunk at least one glass. But they don’t know how many any of the other 3 had drunk. They are big on saying more with less. Everyone listens when anyone speaks. And they don’t lie to each other.
The first one tells the second one: I haven’t drunk more than you.
The second one turns to the third one and says: I haven’t drunk more than you.
The third one tells the fourth: I haven’t drunk more than you.
And the fourth one says: Figured out now how many drinks each of us had.
And the other three say: Figured out now how many drinks each of us had.
How many drinks did each have, and how did they figure it out?
100 emperors and 100 prime ministers gather for a meeting. An uninvited learned, influential, and wise guy shows up and tells the emperors:
“You emperors are going to end up fighting each other and get destroyed. Because there is at least one prime minister among the 100 here, who is a cheat and a spy. Find the cheat(s) and kill them if you don’t want all to end up dead.”
The emperors respect and trust the guy so they do as they are told. They lock themselves in 100 prison cells. In each cell, one emperor and their prime minister. The instructions to the emperors:
1. You don’t know if your own prime minister is a cheat, but you know every other prime minister who’s a cheat.
2. You’ve got 100 days to figure this out. You’ll kill your prime minister if you find them guilty on the same day you find them guilty.
3. You can only communicate with your prime minister because only the two of you will be in the cell.
4. But, you’ll know if a prime minister is killed. You’ll hear their screams in pain as they die.
5. Once every cheat has been slain, the cells will unlock.
6. If you can’t figure this out in 100 days, you’re not smart enough to be an emperor, so you’ll remain locked in the cells forever.
Turns out the wise guy was right. And the emperors find the truth. How?
This is a sales copy trying to convince you to pay for my drink.
