Falling Baby
How can a baby fall out of a 30-story building onto the ground and still be alive?
SOLUTION
The baby fell from the first floor.
Category: Brain Teasers
A collection of Math, Chess, Detective, Lateral, Insight, Science, Practical, and Deduction puzzles, carefully curated by Puzzle Prime.
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The Number in the Yellow Circle
Which is the missing number in the yellow circle?
SOLUTION
The missing number is 12. Each number is equal to the sum of the digits of the numbers pointing towards it.
Vinculus Puzzles
Circles are particles and lines joining them are bonds. The objective is to find all the hidden values, following these four rules:
- Particle values must be the sum of their bond values.
- Particles can have the following values: 0, 1, 2, 4, 8, 12, 16.
- Bonds can have the following values: 0, 1, 2, 4.
- If two particles have the same value, the bond between them must have value 0.
EASY 
MEDIUM 
HARD
SOLUTION
The solutions are shown below.
FEATURED
Jugs with Water
You have a 3 liter jug, a 5 liter jug, and an infinite amount of tap water. How can you measure exactly 4 liters of water using the jugs?
SOLUTION
Call the 3 liter jug “small” the 5 liter jug “large”.
- Fill the large jug with water.
- Pour 3 liters of water from the large jug into the small jug.
- Empty the small jug with water.
- Pour the remaining 2 liters of water from the large jug into the small jug.
- Fill the large jug with water.
- Pour water from the large jug into the small jug, until the small jug is full.
Now there are exactly 4 liters of water in the large jug.
A Good Bet
Someone tells you: “I’ll bet you $1 that if you give me $3, I will give you $5 in return”. Is this a good bet?
SOLUTION
You should not accept the bet and give him $3. If the person gives you the $5, then you would have given him $1+$3=$4, and you would make a profit of $1. However, the person can simply not give you anything and you will lose $3-$1=$2.
Scoring penalties
At some point in Leonel Messi’s career, the football player had less than 80% success when performing penalty kicks. Later in his career, he had more than 80% success when performing penalty kicks. Show that there was a moment in Leonel Messi’s career
SOLUTION
Let us see that it is impossible for Messi to jump from under 80% success rate to over 80% success rate in just one attempt. Indeed, if Messi’s success rate was below 80% after N attempts, then he scored at most 4N/5 – 1/5 = (4N-1)/5 times. If his success rate was above 80% after N+1 attempts, then he scored at least 4(N+1)/5 + 1/5 = (4N-1)/5 + 6/5 times. However, Messi can not score more than one goal in a single attempt, which completes the proof.
Five Men in the Rain
There were five men going to church and it started to rain. The four that ran got wet and the one that stood still stayed dry.
SOLUTION
Four of the men were carrying a dead man in a coffin to his funeral.
What Day Would Yesterday Be
What day would yesterday be if Thursday was 4 days before the day after tomorrow?
SOLUTION
The answer is Friday.
A Dream Man at a Funeral
While at her own mother’s funeral, a girl meets a guy she doesn’t know. She thinks the guy is amazing – her dream man – and is pretty sure he could be the love of her life. However, she never asks for his name or number and afterwards can not find anyone who knows who he is. A few days later, the girl kills her own sister.
Why did she do it?
SOLUTION
The girl assumed the man was a family friend, so she decided he would come also to the funeral of her sister.
A Note in a Math Class
A boy receives a small note from a girl during his math class. He unfolds the note and sees the following expression.
What does it mean?
SOLUTION
If you fold the note the other way around, the message “I LOVE YOU” appears.
