Riddles and Brain Teasers

Six One Seven and Nine to Make Twenty Four

How can the numbers 6, 1, 7 and 9 be arranged to make 24?

91 – 67 = 24
(9 – 6) × (1 + 7) = 3 × 8 = 24

Leaves That Don’t Fall

I have wood but no bark,
And leaves that don’t fall,
I am made up of branches,
and come in sizes of all.

I am completely devoured many times,
over and over by a worm of a kind.
If you want to know the answer of mine,
look for the secret that I’ve stored inside.

What am I?

Show the answer »

A library or bookstore.

Posted in Riddles

Tagged with What am I?

Three Letter Word Completion

What three letter word can complete the below words?

B___
D___
M___ET
P___ING
SH___

Show the answer »

Ark, which produces: bark, dark, market, parking, shark.

Posted in Brain Teasers

Touch Me and I’m Gone

Touch me and I’m gone,
But to you I belong.
I stay with you for life,
But I am not seen by your wife.

What am I?

Show the answer »

Your reflection in the water.

Posted in Riddles

Ten Times Two is 0218

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

Show the answer »

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

A House With No Doors

I am in a house with no doors. There are people inside but give no reply. Who am I?

Show the answer »

A fish. A fish bowl or aquarium is the fish’s house and the people inside are the decorative divers that offer no reply (one might ask how the fish knows, given that they aren’t a talkative bunch themselves).

Posted in Riddles

AADFJJ

A A D F J J J M M N ?

What comes next in the series?

Show the answer »

O S. The series contains the first letter of each month in alphabetical order (April, August, December, February, January, July, June, March, May, November). O and S represent the remaining 2 months, October and September.

Posted in Brain Teasers

Tagged with sequence

Don’t Get a Goat

On a game show there are three closed doors – one hides a car and the other two conceal a goat. The contestant selects a door, which remains closed, and the host, knowing where the car is hidden, reveals a goat behind one of the remaining two doors. The contestant is then given the option to switch doors or stay with the one they originally selected. What should the contestant do to have the best chance of winning the car?

Show the answer »

The contestant should switch doors, which doubles the chance of winning the car. Initially there is a 2/3 chance of picking a goat, but once the other goat is revealed, switching to remaining door gives the contestant a better chance of winning the car. This is known as the Monty Hall Problem and can be very unintuitive.

Posted in Brain Teasers

One Way I’m Feeling Normal

One way I’m feeling normal,
Another I’m extremely thin,
I could be a punishment,
Or the type who always wins.

I’m free from all impurity,
And you may have divined,
I have a keen edge,
But of course I am refined.

Show the answer »

Fine.The riddle refers to a variety of meanings of the word fine.Feeling normal refers to when you feel fine.
Extremely thin refers to a fine thread.
A punishment refers to being charged a fee.
The one who wins refers to an athlete who is physically trained and hardened close to the limit of efficiency.
Free from impurity refers to measuring the fineness of precious metals.
A keen edge refers to a knife with a fine edge.
Refined refers to fine manners or elegance.

Fine.

The riddle refers to a variety of meanings of the word fine.

Feeling normal refers to when you feel fine.
Extremely thin refers to a fine thread.
A punishment refers to being charged a fee.
The one who wins refers to an athlete who is physically trained and hardened close to the limit of efficiency.
Free from impurity refers to measuring the fineness of precious metals.
A keen edge refers to a knife with a fine edge.
Refined refers to fine manners or elegance.

Posted in Riddles

How to Save Gas

If you could chose to increase the average fuel economy of a car, which of these would save the most fuel?

1. 10mpg -> 12mpg
2. 12mpg -> 15mpg
3. 15mpg -> 20mpg
4. 20mpg -> 30mpg
5. 30mpg -> 60mpg

Show the answer »

It turns out they all save the same amount of fuel.If you travel 100 miles:100 / 10 = 10 gallons used
100 / 12 = 8 1/3 gallons used10 – 8 1/3 = 1 2/3 gallons saved100 / 30 = 3 1/3 gallons used
100 / 60 = 1 2/3 gallons used3 1/3 – 1 2/3 = 1 2/3 gallons saved

It turns out they all save the same amount of fuel.

If you travel 100 miles:

100 / 10 = 10 gallons used
100 / 12 = 8 1/3 gallons used

10 – 8 1/3 = 1 2/3 gallons saved

100 / 30 = 3 1/3 gallons used
100 / 60 = 1 2/3 gallons used

3 1/3 – 1 2/3 = 1 2/3 gallons saved

Posted in Brain Teasers

More ›