Eight Eights
Hint:
Find That Tennis Ball
You have 7 tennis balls that are all identical but one of them is slightly lighter than the others.
Using a balance scale and only two separate weightings, how can you find the light tennis ball?
Using a balance scale and only two separate weightings, how can you find the light tennis ball?
Hint:
Put three of the balls on each side. If they are even the ball that wasn't weighed is the light one. If they aren't even the side that is lighter has the light ball. Of these three balls, one should be put on each side. If the sides are even than the other ball is the light one. If they aren't even the one that is lighter is the ball you're looking for. Did you answer this riddle correctly?
YES NO
YES NO
Brownie Currency
You're going to a friends house and want to give them some brownies. On the way to their house you cross 5 bridges. At each bridge you must pay a toll of half of your brownies to the owner. But they are all very nice and give you back a brownie from what you give them.
How many brownies must you start with to give your friend 2 brownies?
How many brownies must you start with to give your friend 2 brownies?
Hint:
Just 2.
Each time you give the owner of a bridge half of your brownies (1 brownie) they give you one back as well. Did you answer this riddle correctly?
YES NO
Each time you give the owner of a bridge half of your brownies (1 brownie) they give you one back as well. Did you answer this riddle correctly?
YES NO
How Many Batteries?
You have a flashlight that takes 2 working batteries. You have 8 batteries but only 4 of them work.
What is the fewest number of pairs you need to test to guarantee you can get the flashlight on?
What is the fewest number of pairs you need to test to guarantee you can get the flashlight on?
Hint:
7. If you break the batteries into 3 groups: Two groups of 3 and one group of 2. By doing this you guarantee that one of the groups has 2 working batteries. Both of the groups of 3 have 3 possible combinations of 2 batteries and the group of 2 only has 1 combination. So, 3 + 3 + 1 = 7 tries at most to find two working batteries. Did you answer this riddle correctly?
YES NO
YES NO
A Knight To The Rescue
A knight comes to a castle where his love is trapped. The castle is surrounded by a square moat that is 10 feet wide (it forms a square around the castle). The knight is able to fashion two 9 foot long planks to cross the moat.
How can he do this?
How can he do this?
Hint:
He puts one plank across the corner of the square (where two sides meet) and puts the other perpendicular to it to form a 'T' shape in the corner allowing him to cross the moat and save his beloved. Did you answer this riddle correctly?
YES NO
YES NO
Which Is Correct?
Hint: What is 9 plus 5?
1 Year Of Chickens
There are five hen and rooster pairs. Each pair has one baby every month.
How many chickens will there be in one year?
How many chickens will there be in one year?
Hint:
It is impossible to know because the chicken's babies could also have babies during this time.
Did you answer this riddle correctly?
YES NO
Did you answer this riddle correctly?
YES NO
Whats The Temperature?
Hint:
273.15 degrees Celsius. When making conversions like this you must convert to the Kelvin scale since it is the only one that works on a scale beginning with 0. Did you answer this riddle correctly?
YES NO
YES NO
How Old Could He Be?
In 1940, a correspondent proposed the following question:
A man's age at death was one twenty-ninth of the year of his birth. How old was he in 1900?
A man's age at death was one twenty-ninth of the year of his birth. How old was he in 1900?
Hint:
He was 44 years old.
From the question you know the man died between 1900 and 1940. We also know his age at death (x) is one twenty-ninth of the year of his birth (29x). If you add his age at death to the year he was born you get the year he died (30x). Only one year between 1900 and 1940 is divisible by 30, 1920 (the year he died). The year he was born can now be found: 1920 * (29/30) = 1856. So in 1900 he was (1900 - 1856) = 44 years old. Did you answer this riddle correctly?
YES NO
From the question you know the man died between 1900 and 1940. We also know his age at death (x) is one twenty-ninth of the year of his birth (29x). If you add his age at death to the year he was born you get the year he died (30x). Only one year between 1900 and 1940 is divisible by 30, 1920 (the year he died). The year he was born can now be found: 1920 * (29/30) = 1856. So in 1900 he was (1900 - 1856) = 44 years old. Did you answer this riddle correctly?
YES NO
What Are The Coins?
Hint:
A nickel and a quarter: one of them isn't a nickel but the other one is Did you answer this riddle correctly?
YES NO
YES NO
Carefully Counting Kids
Hint:
Three Feet
Hint:
Skipping The Pop Quiz
A teacher decides to give a pop quiz one day but all of her students refuse to take the quiz thinking that the teacher will call off the quiz. She can give only one of these students a detention for skipping the quiz. All of the students know each other's names and if a student knows he/she is getting a detention they take the quiz.
How can she threaten her students with the single detention so they all take the quiz?
How can she threaten her students with the single detention so they all take the quiz?
Hint:
She tells them that she will give the student who skips the quiz whose name comes first alphabetically a detention. This student won't skip because they know they are getting a detention if they do. The next person alphabetically will then know that they will get a detention so they won't skip either, and so on. Did you answer this riddle correctly?
YES NO
YES NO
Owl University
Hint:
Stuck With Me Forever Riddle
Your finger fits right in it. You play with it when you're bored. Once you're married, you're stuck with the same one forever. What is it?
Hint:
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