The Secret Lair

A secret lair has a code to only allow members to enter. The person wanting to enter says a random number, then is told a number in response. In order to enter they must say the correct third number. Here are sequences that allowed entrance.

1 3 5
27 11 6
9 4 4

What’s the third number of this series?

16 7 ?

Five because s-e-v-e-n has 5 letters. The first number can be anything, the second number is the number of letters in the first number, and the third number is the number of letters in the second number.

Posted in Brain Teasers

Subtracting Ten From A Hundred

How many times can you subtract 10 from 100?

Only once. The next time you’d be subtracting 10 from 90.

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Twenty One Points Divide And Dance

Twenty one points divide and dance,
Twirling and leaping about,
Ladies, Romans and knights of France,
Craving a victor’s rout,
Wrought of wood, ivory or bone,
An exciting yet vicious pursuit,
Ancient, forbidden and crooked,
All in search of the loot.

A die. The standard die has 21 pips (or points), divided up on the six sides of the die which dance around when rolled. Ladies, knights and Romans all played dice as a pastime (though not together). Dice can be made of wood, ivory and bone, among other materials. Dice have been used in Asia since before recorded history and many governments tried unsuccessfully to outlaw the game. Professional gamblers were common and often used loaded dice. Desperate German chaps even bet their own liberty on a single roll of the dice.

Posted in Riddles

Five Three Two

What is the answer to the last equation?

5 3 2 = 151012
9 2 4 = 183662
8 6 3 = 482466
5 4 5 = 202504
7 2 5 = ?

10000 × (x × y) + 100 × (x × z) + transpose_digits(x × y + y × z)

transpose_digits() just swaps the digits

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Who Is Silent In Parliament?

Who is silent in Parliament?

The letter i, which is the only silent letter in the word Parliament.

Posted in Riddles

Two Three Four Fifteen

What is the missing number?

2 3 4 15 12
3 4 5 28 20
4 5 6 45 30
5 6 7 66 42
6 7 8 ?? 56

91. To get the number in the fourth column, you add the numbers in column 1 and 2, then multiply by the number in column 2. f(n,m) = (n + m) * m
For example, f(2,3) = (2 + 3) * 3 = 15. Thus f(6,7) = (6 + 7) * 7 = 91

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Ground Not For Thy Daily Bread

Ground not for thy daily bread,
Leave me in my scented bed,
Ignore me not, lest I doth wither,
My name I leave you to consider.

A flower. The soil they grow in is not used for food, like wheat to make bread, but for their smell. A neglected flower will wither.

Posted in Riddles

How Old Is Amir?

Amir has three children. One is the same age as the first number in his age, another is the same age as the second number in his age, and the third is the same age as the sum of the two numbers in his age. None of the children are the same age and the total of everyone’s ages is 45. How old is Amir?

27. His children are 2, 7, and 9.

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Square Root Equations

Arrange the digits 1 through 9 into an equation so that the first number is the square root of the second number. (Two possible variations)

5672 = 321,489

OR

8542 = 729,316

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Little Cat’s Feet

It comes in on little cat’s feet,
Is neither sour, nor sweet.
Hovers in the air,
And then is not there.

Fog or mist

Posted in Riddles