Math & Number Riddles

Five hundred begins it, five hundred ends it, Five in the middle is seen; First of all figures, the first of all letters, Take up their stations between. Join all together, and then you will bring Before you the name of an eminent king.

There is a party of 100 high-powered politicians. All of them are either honest or liars. You walk in knowing two things: - At least one of them is honest. - If you take any two politicians, at least one of them is a liar. From this information, can you know how many are liars and how many are honest?

Three people check into a room. The bill is $30. They split it 3 ways. Later on the hotel realizes they should have charged $25 so they send a bellhop to return $5. The bellhop realizes he can't split $5 3 ways to he gives each person $1 and keeps $2. They have now paid $9 each for the room, the bellhop has $2. $27 + $2 = $29 What happened to the last $1 considering $30 was originally paid.

Two is company and 3 is a crowd. What is 4 and 5?

What number do you get when you multiply all of the numbers on a telephone's number pad?

There is a chain nailed to the wall. The chain is 10 feet long and the centre of the chain dips down 5 feet from where each side of the chain is nailed to the wall. How far are the 2 ends of chain from each other?

If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets?

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 child playing on the beach had 6-1/6 sand piles in one place and 3-1/3 in another. If he put them together, how many sand piles would he have?

When is 1500 plus 20 and 1600 minus 40 the same thing?

What is the largest possible number you can write using only 2 numbers - just 2 numbers, no other mathematical symbols?

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?

An interesting formula for generating a good many (but not all) primes is n2 + n + 41. If we plug in consecutive integers 1, 2, 3, etc., at least up to a certain point, we can generate prime numbers. Give an integer for which the formula fails.

100 passengers are boarding a plane with 100 seats. The first passenger in line has lost his boarding pass and chooses a random seat to sit in. Each subsequent passenger takes their assigned seat if it is unoccupied. Otherwise, they take a random unoccupied seat. What is the probability that the last passenger will find their seat unoccupied?

When I take five and add six, I get eleven, but when I take six and add seven, I get one. What am I?

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 basket contains 5 apples. Do you know how to divide them among 5 kids so that each one has an apple and one apple stays in the basket?

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?

If Mr. Flynn is 90 centimeters plus half his height, how tall is he?

One brick is one kilogram and half a brick heavy. What is the weight of one brick?