Maths Set Theory Puzzle

In a school, there are four subjects. Seventy percent of students study English, seventy five percent of students study Science, eighty five percent of students study Mathematics and eighty percent of students study Spanish.

Can you calculate the percentage of students that study all four subjects?




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A man is approaching a broad and barren land. He has a package with him. If somehow, he is unable to open the package before reaching the land, he will die.

Can you guess what is present in the package?

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Once upon a time, there was a castle on a square island. The entire island was surrounded by a 14m wide trench. The Romans had wanted to invade the castle and had brought a few wooden planks along with them to facilitate themselves in crossing the moat. The planks were however found to be only 13m long.

The Romans still managed to cross the trench. How did they do it?

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I ask Joseph to pick any 5 cards out of a deck with no Jokers.

He can inspect then shuffle the deck before picking any five cards. He picks out 5 cards then hands them to me (Jack can't see any of this). I look at the cards and I pick 1 card out and give it back to Joseph. I then arrange the other four cards in a special way, and give those 4 cards all face down, and in a neat pile, to Jack.

Jack looks at the 4 cards i gave him, and says out loud which card Joseph is holding (suit and number). How?

The solution uses pure logic, not sleight of hand. All Jack needs to know is the order of the cards and what is on their face, nothing more.

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Dr Doom invited a group of puzzle fanatics to a party which was oriented toward having puzzle-oriented games. At night, he introduced the guests to a 'unique riddle'. A prize was offered to the one who solved it first.

The guests included six people named Tom Paul, Fox Obama, Jeremy Reener, Alex Murphy, Prim Pastor, and Ellen Page. The winner of the 'unique riddle' contest was to be announced after the dinner. So Dr. Doom stood up and started the announcement:

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Spot what is wrong here in below Picture?

Spot the wrong in Picture

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Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

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A mother bought three dress for her triplets daughters(one for each) and put the dresses in the dark. One by one the girls come and pick a dress.
What is the probability that no girl will choose her own dress?

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A generous owner of a company decided to give a bonus of $45 to every man and $60 to every woman on his birthday. But only one-ninth of the men and one-twelfth of the women were present to take the bonus.

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John is pretty weird. He likes toffees but hates chocolates. He loves books but never reads. He likes to build his troops in an online game but does not proceed with the war. He likes to go swimming but is afraid of water.

Seeking this behaviour, can you tell whether he likes balloons and parties?

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Once upon a time, there was a bus conductor who was extremely rude to all the passengers. On a certain day, a young and charming lady tried boarding the bus. But he did not stop the bus. As a result, the girl came under the bus and was killed. The agitated passengers took the conductor to the police station. The police took him to the court for trial. In the court, the judge gave him death sentence.

He is then taken to the electrocution chamber. In that room, there is a chair in the center of the room and a banana peel lies just behind the chair. The conductor is strapped to that chair and is being exposed to a high voltage current. But to everyone�s surprise, he is able to survive through the current that is enough to kill two people at once. The judge decides that it is a miracle and sets the conductor free.

The conductor then returns back to his profession. After a few months, a middle aged lady tries to board the bus. The conductor does not stop the bus and as a result the lady gets run over by the bus which kills her on the spot. The agitated passengers take him to the police. The police takes him to the court for the trial. In the court, the judge decides for capital punishment for the conductor.

The conductor is taken to the electrocution chamber again. In that chamber, there is a chair in the middle of the room and a banana peel lies behind the chair. He is strapped to the chair and exposed to a high voltage. To everyone�s surprise, he survives again. Thus, the judge sets him free.

The conductor returns back to his profession. After a few months. An old lady tries to board the bus. The bus conductor after remembering his previous actions, stops the bus. But unfortunately, the old lady slips while climbing up the bus and dies due to his injuries. The passengers take him to the police again. The police takes him back to the court. Though the judge knows that he is not guilty, he sentences him to death knowing his previous record.

The conductor is taken to the electrocution chamber again. He is strapped to the chair in the center of the room behind which, there is a banana peel. He is exposed to the current and this time he is killed instantly.

Why did he die this time and not the previous times?

Long Funny Riddle

Asked by Neha on 16 Mar 2023

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Amazing Facts

Word ladder puzzle

The word ladder puzzle was invented by Lewis Carroll, author of Alice’s Adventures in Wonderland.