2303.HardLogic Riddle

George, Helen, and Steve are drinking coffee. Bert, Karen, and Dave are drinking soda. Is Elizabeth drinking coffee or soda?

  • A.Soda
  • B.Neither
  • C.Both
  • D.Coffee. The letter E appears twice in her name, as it does in the names of the others drinking coffee.
Answer: Coffee. The letter E appears twice in her name, as it does in the names of the others drinking coffee.

George, Helen, and Steve (the coffee drinkers) each have the letter "e" appearing twice in their names, matching Elizabeth's name, which also contains two "e"s -- so she is drinking coffee too.

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2304.MediumLogic Riddle

MT_TF_S What are the missing letters? Why?

  • A.A and S
  • B.T and F
  • C.M and W
  • D.W and S, for the days of the week (Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday).
Answer: W and S, for the days of the week (Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday).

The letters given (M, T, _, T, F, _, S) are the first letters of the seven days of the week, with Wednesday's W and Sunday's S missing from the blanks.

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2305.HardLogic Riddle

A mother had five boys Marco, Tucker, Webster and Thomas. Was the fifth boys name Frank, Evan or Alex?

  • A.Evan
  • B.Alex
  • C.Either Evan or Alex
  • D.Frank. Each child's first name begins with the first letters of the days of the week: M, T, W, T, Frank.
Answer: Frank. Each child's first name begins with the first letters of the days of the week: M, T, W, T, Frank.

Look at just the first letters of each brother's name to spot the days-of-the-week pattern.

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2307.HardLogic Riddle

There is a word in the English language in which the first two letters signify a male, the first three letters signify a female, the first four signify a great man, and the whole word, a great woman. What is the word?

  • A.Heroism
  • B.Warrior
  • C.Champion
  • D.Heroine
Answer: Heroine

"He" signifies a male, "Her" signifies a female, "Hero" signifies a great man, and the full word "Heroine" signifies a great woman -- each stage of the word builds in meaning exactly as described.

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2310.HardMath Riddle

There are 500 coffins and 500 men who need them. The undertaker asks the first man to go to every coffin and open them. Then he tells the second man to go to every one and close it. The third one goes to every third coffin and so on. How many are open?

  • A.500
  • B.250
  • C.1
  • D.22
Answer: 22

Only coffins with an odd number of divisors stay open in the end - the perfect squares - and there are exactly 22 perfect squares (1 squared through 22 squared) at or below 500.

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2311.HardMath Riddle

How do you go from 98 to 720 using just one letter?

  • A.Add a "7" in front of 98
  • B.Multiply 98 by itself
  • C.Add an "s" to make it plural
  • D.Add an "x" between "ninety" and "eight": Ninety x Eight = 720
Answer: Add an "x" between "ninety" and "eight": Ninety x Eight = 720

Spelling out "98" as "ninety eight" and inserting the letter x between the words creates "ninety x eight," which multiplies to 720.

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2316.HardMath Riddle

In a bicycle race, the man who came two places in front of the last man finished one ahead of the man who came fifth. How many contestants were there?

  • A.5 contestants
  • B.7 contestants
  • C.8 contestants
  • D.There were 6 contestants. The man came in 4th place.
Answer: There were 6 contestants. The man came in 4th place.

If he's two places ahead of last (6th) he's in 4th, and finishing one ahead of 5th place also places him in 4th -- both conditions align only when there are 6 total contestants.

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2317.HardMath Riddle

My daughter has many sisters. She has as many sisters as she has brothers. Each of her brothers has twice as many sisters as brothers. How many sons and daughters do I have?

  • A.Three daughters and four sons
  • B.Four daughters and four sons
  • C.Three daughters and three sons
  • D.Four daughters and three sons. Each daughter has 3 sisters and 3 brothers, and each brother has 2 brothers and 4 sisters.
Answer: Four daughters and three sons. Each daughter has 3 sisters and 3 brothers, and each brother has 2 brothers and 4 sisters.

With 4 daughters and 3 sons, each daughter has 3 sisters and 3 brothers (equal), and each son has 2 brothers and 4 sisters (twice as many sisters as brothers) -- satisfying both conditions.

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2320.HardMath Riddle

There are 25 red balls, 47 green balls and 3 blue balls in a basket. There is a blind man. What is the minimum number of balls that the blind man has to pick to make sure that there are at least 2 balls of different colors?

  • A.3 balls
  • B.26 balls
  • C.4 balls
  • D.48 balls. There is a small chance he may pick up 47 green balls in a row.
Answer: 48 balls. There is a small chance he may pick up 47 green balls in a row.

In the worst possible case, the blind man could draw all 47 green balls in a row before finally getting a red or blue one, so 48 draws guarantee at least two different colors.

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2325.HardMath Riddle

The combined age of Jack and John is 49. Jack is twice as old, as John was when Jack was as old as John is now. How old are the brothers?

  • A.Jack is 30 and John is 19
  • B.Jack is 25 and John is 24
  • C.Jack is 35 and John is 14
  • D.Jack is 28 and John is 21.
Answer: Jack is 28 and John is 21.

Jack's age (28) is twice what John's age was seven years ago (14), which is exactly the gap between their ages now (28 - 21 = 7), and 28 + 21 = 49 as required.

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2326.MediumMath Riddle

How many days are there in 4 years?

  • A.1460
  • B.1462
  • C.1464
  • D.1461. (365 x 4) + 1, because one of the years is a leap year.
Answer: 1461. (365 x 4) + 1, because one of the years is a leap year.

Four years of 365 days would total 1,460 days, but one of the four is a leap year with an extra day, bringing the true total to 1,461.

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2328.MediumMath Riddle

If you toss a coin 10 times and it lands heads up every time, what are the chances it will land heads up if you toss it again?

  • A.Very high, near 100%
  • B.Very low, near 0%
  • C.Exactly 90%
  • D.There is a 50/50 chance of each toss being either heads or tails. The previous toss does not impact the next toss.
Answer: There is a 50/50 chance of each toss being either heads or tails. The previous toss does not impact the next toss.

A fair coin has no memory -- each flip is an independent event with exactly a 50% chance of heads, regardless of past results.

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2329.MediumMath Riddle

In a lake, there is a patch of lily pads. Every day, the patch doubles in size. If it takes 48 days for the patch to cover the entire lake, how long would it take for the patch to cover half the lake?

  • A.24 days
  • B.36 days
  • C.47.5 days
  • D.The patch doubles in size every day, so on the 47th day the patch will be half the size it is on the 48th day.
Answer: The patch doubles in size every day, so on the 47th day the patch will be half the size it is on the 48th day.

Since the patch's size doubles every single day, it must have covered exactly half the lake just one day before it covered the whole lake - day 47.

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2330.HardMath Riddle

Dean Sam and Castiel are three brothers. Interestingly their current age is prime. What's more interesting that difference between their ages is also prime. How old are they?

  • A.2, 3, and 5
  • B.3, 5, and 7
  • C.2, 5, and 11
  • D.Sam is 2, Dean is 5, and Castiel is 7. The age differences (5-2=3, 7-5=2, 7-2=5) are all prime numbers.
Answer: Sam is 2, Dean is 5, and Castiel is 7. The age differences (5-2=3, 7-5=2, 7-2=5) are all prime numbers.

Ages 2, 5, and 7 are all prime numbers, and the differences between them - 3, 2, and 5 - are also all prime, satisfying every condition in the riddle.

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2331.MediumMath Riddle

There are two fathers and two sons. They walk into a candy store and each buys a candy bar for 50 cents. The total for all of the candy bars was $1.50. How is that possible?

  • A.One father bought two bars
  • B.They got a discount
  • C.One son didn't buy one
  • D.There was a grandfather, a father and a son.
Answer: There was a grandfather, a father and a son.

With a grandfather, father, and son, the middle person counts as both a father and a son, giving 'two fathers and two sons' among only three people who buy just three candy bars.

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2333.HardMath Riddle

How can you give someone $83 using exactly 7 bills, without using any one dollar bills?

  • A.1 fifty, 2 twenties, 5 ones
  • B.8 ten dollar bills and change
  • C.1 hundred bill and change back
  • D.Give them 1 fifty dollar bill, 1 twenty dollar bill, 1 five dollar bill and 4 two dollar bills.
Answer: Give them 1 fifty dollar bill, 1 twenty dollar bill, 1 five dollar bill and 4 two dollar bills.

A $50 bill, a $20 bill, a $5 bill, and four $2 bills together total $83 using exactly seven bills and no $1 bills.

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2338.HardMath Riddle

A bat and a ball cost $1.10. The bat costs one dollar more than the ball. How much does the ball cost?

  • A.10 cents
  • B.15 cents
  • C.1 cent
  • D.The ball costs 5 cents, not 10 cents. One dollar more than 10 cents is $1.10, but $1.10 + 10 cents would be $1.20. One dollar more than 5 cents is $1.05, and the sum of that is $1.10.
Answer: The ball costs 5 cents, not 10 cents. One dollar more than 10 cents is $1.10, but $1.10 + 10 cents would be $1.20. One dollar more than 5 cents is $1.05, and the sum of that is $1.10.

If the ball costs 5 cents, the bat costs $1.05 (one dollar more), and together they total $1.10 -- the common wrong intuitive answer of 10 cents doesn't satisfy the 'one dollar more' condition.

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2353.MediumGood Riddle

A murderer is condemned to death. He has to choose between three rooms. The first is full of raging fires, the second is full of assassins with loaded guns, and the third is full of lions that haven't eaten in 3 years. Which room is safest for him?

  • A.The first room
  • B.The second room
  • C.None are safe
  • D.The third room, because those lions haven't eaten in three years, so they are dead.
Answer: The third room, because those lions haven't eaten in three years, so they are dead.

Lions that haven't eaten in three years would have starved to death long before now, so the 'lion-filled' third room actually poses no danger at all.

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2362.HardGood Riddle

In 1990, a person is 15 years old. In 1995, that same person is 10 years old. How can this be?

  • A.They lied about their age
  • B.They had a birthday reversal
  • C.It's a leap year error
  • D.The person was born in 2005 B.C. (Before Christ). Therefore, he was 5 years old in 2000 B.C., 10 in 1995 B.C., and 15 in 1990 B.C.
Answer: The person was born in 2005 B.C. (Before Christ). Therefore, he was 5 years old in 2000 B.C., 10 in 1995 B.C., and 15 in 1990 B.C.

The years given are B.C. dates, which count downward, so a birth in 2005 B.C. makes the person 15 in 1990 B.C. and 10 in 1995 B.C.

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2380.HardGood Riddle

An apple is 40 cents, a banana is 60 cents and a grapefruit is 80 cents. How much is a pear?

  • A.60 cents
  • B.20 cents
  • C.80 cents
  • D.40 cents. The price of each fruit is calculated by multiplying the number of vowels by 20 cents.
Answer: 40 cents. The price of each fruit is calculated by multiplying the number of vowels by 20 cents.

Each fruit's price equals its number of vowels times 20 cents -- apple (2 vowels) = 40c, banana (3 vowels) = 60c, grapefruit (4 vowels) = 80c, and pear (2 vowels) = 40c.

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2396.HardWho Am I Riddle

I follow the orders of only two. I respect the work of only two. I am in constant battles with many, Though one surpassed them all. With forces joined, We created hell, Until our mutual enemy fell. Who am I?

  • A.Dobby
  • B.Voldemort
  • C.Filch
  • D.Peeves
Answer: Peeves

Peeves the Poltergeist, from the Harry Potter series, answers only to the Bloody Baron and the Hogwarts Headmaster, causes mischief throughout the castle, and joined forces with others to help bring down Voldemort during the Battle of Hogwarts.

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2397.HardWho Am I Riddle

Although I'm not an insect, some people found me very difficult to exterminate. They called me something like 'insane priest.' The first half of my name means the same as 'scrape,' & my last three letters are a metal. Who am I?

  • A.Stalin
  • B.Napoleon
  • C.Hitler
  • D.Rasputin
Answer: Rasputin

The clues spell out "Rasputin": the first part evokes "raze" (scrape/tear down) and the last three letters, "tin," are a metal. Grigori Rasputin was infamous for surviving repeated assassination attempts, making him legendarily "difficult to exterminate."

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