Riddles and Brain Teasers

From Diner to Menus

How can you go from DINER to MENUS, changing one letter at a time and forming another English word in each step?

DINER
MINER
MINES
MINUS
MENUS

Another option is:
DINER
DINES
MINES
MINUS
MENUS

Posted in Brain Teasers

A family photo has the following:
1 grandfather, 1 grandmother
2 fathers, 2 mothers
6 children, 4 grandchildren
2 brothers, 2 sisters
3 sons, 3 daughters
1 father-in-law, 1 mother-in-law
1 daughter-in-law

It could show 29 different people, but what is the smallest number of people if could have?

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Eight. 4 children, their mother and father and one set of grandparents.

Posted in Brain Teasers

Ten Times Two is 0218

10 × 2 = 0218
20 × 2 = 1421
30 × 2 = 1632
40 × 2 = ?

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2840.This makes the first column the start of the Fibonacci series: 0, 1, 1, 2.
The second column is the even numbers: 2, 4, 6, 8
The third column is counting up by ones: 1, 2, 3, 4
And the last column is the answer in the first row in reverse: 8, 1, 2, 0.Don’t ask what 50 × 2 equals. I have no idea. :)Thanks to Jim for helping with the solution.

2840.

This makes the first column the start of the Fibonacci series: 0, 1, 1, 2.
The second column is the even numbers: 2, 4, 6, 8
The third column is counting up by ones: 1, 2, 3, 4
And the last column is the answer in the first row in reverse: 8, 1, 2, 0.

Don’t ask what 50 × 2 equals. I have no idea. :)

Thanks to Jim for helping with the solution.

Posted in Brain Teasers

Tagged with Series

Against the Rules for You to Play Fair

It’s against the rules for you to play fair,
I always win but you don’t care,
I’ve ruined lives and crushed dreams,
But the allure is too much it seems.

What am I?

Show the answer »

A casino. If you use methods to make the odds more fair to you, they kick you out. The house always wins, yet people continue to play. Gambling has ruined countless lives and crushed dreams of making millions, but the hope of winning continues to draw people in.

Posted in Riddles

Tagged with What am I?

It Cannot Be Seen and Weighs Nothing

It cannot be seen, it weighs nothing, but when put into a barrel, it makes it lighter. What is it?

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A hole.

Posted in Riddles

Four Gallons From Two Buckets

You have two buckets. One holds exactly five gallons and the other three gallons. How can you measure exactly four gallons of water into the five gallon bucket?

Assume you have an unlimited supply of water and that there are no measurement markings of any kind on the buckets.

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Fill the 3-gallon bucket.

Pour the 3 gallons of water into the 5-gallon bucket

Fill the 3-gallon bucket again.

Fill up the 5-gallon bucket with the 3-gallon bucket, leaving you with 1 gallon left in the 3-gallon bucket.

Empty out the 5-gallon bucket.

Pour the remaining 1 gallon of water from the 3-gallon bucket into the 5-gallon bucket.

Fill the 3-gallon bucket.

Pour the 3 gallons of water from the 3-gallon bucket into the 5-gallon bucket leaving you with 4 gallons of water in the 5-gallon bucket.

Alternate solution:

Fill up the 5 gallon bucket

Pour it into 3 gallon bucket, leaving 2 gallons

Empty out the 3 gallon bucket

Pour the 2 gallons in the 5 gallon bucket into the 3 gallon bucket

Fill up the 5 gallon bucket and pour it into the 3 gallon bucket until it’s full, leaving 4 gallons in the 5 gallon bucket.

Fill the 3-gallon bucket.
Pour the 3 gallons of water into the 5-gallon bucket
Fill the 3-gallon bucket again.
Fill up the 5-gallon bucket with the 3-gallon bucket, leaving you with 1 gallon left in the 3-gallon bucket.
Empty out the 5-gallon bucket.
Pour the remaining 1 gallon of water from the 3-gallon bucket into the 5-gallon bucket.
Fill the 3-gallon bucket.
Pour the 3 gallons of water from the 3-gallon bucket into the 5-gallon bucket leaving you with 4 gallons of water in the 5-gallon bucket.

Alternate solution:

Fill up the 5 gallon bucket
Pour it into 3 gallon bucket, leaving 2 gallons
Empty out the 3 gallon bucket
Pour the 2 gallons in the 5 gallon bucket into the 3 gallon bucket
Fill up the 5 gallon bucket and pour it into the 3 gallon bucket until it’s full, leaving 4 gallons in the 5 gallon bucket.

Posted in Brain Teasers

A Woman in a Boat

There’s a woman in a boat, on a lake, wearing a coat.
If you want to know her name, it’s in the riddle I just wrote.

What’s the woman’s name?

Show the answer »

“Theresa” is the woman’s name. (There’s a = Theresa)

An alternative answer is “There”.

Posted in Riddles

What Do You Serve?

What do you serve that a polite recipient would immediately send back?

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A ball, when you’re playing tennis, volleyball, table tennis, etc.

Posted in Riddles

Bank Wait Times

Suppose a small bank has one teller and customer transactions take 10 minutes on average. With 5.8 customers arriving per hour, what is the expected wait time? What would it be if you added a second teller?

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With one teller, customers will wait nearly five hours on average. But adding a second teller makes the wait go down to 3 minutes.Thanks to John D. Cook for this one.

With one teller, customers will wait nearly five hours on average. But adding a second teller makes the wait go down to 3 minutes.

Thanks to John D. Cook for this one.

Posted in Brain Teasers

More You Take Away, The Bigger I Get

The more you take from me, the bigger I get. What am I?

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A hole.

This is quite similar to It Cannot Be Seen and Weighs Nothing.

Posted in Riddles

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