Two Two Four Sequence

What number comes next?

2, 2, 4, 12, 48, ___

240. To get the number, multiply the previous number in the series by its position. 48 is in the 5th position, so 48 × 5 = 240

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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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Lying On Certain Days of the Week

Angel lies on Mondays, Tuesdays and Wednesdays but tells the truth the rest of the week.

Brenda lies on Thursdays, Fridays and Saturdays, but tells the truth every other day.

Angel says, “Yesterday I was lying.”

Brenda replies, “So was I.”

What day was it?

Thursday.

Putting the information in a table makes it easier to solve. We’ll use A for Angie, B for Brenda, T for truth and F (false) for lying.

 SMTWThFS
ATFFFTTT
BTTTTFFF

To begin with, there aren’t any days where both of them told the truth and lied the day before, so we know one of them must be lying.

So we have two options, either Angel is lying or Brenda is.

Option 1. Angel is lying.

In order for this to be the case, she needs to be lying today and telling the truth yesterday, so we need two days in a row with T F. And if Brenda is telling the truth, she would need two days with F T. That means we’re looking for two days that have

Angie:  T F
Brenda: F T

Option 2. Brenda is lying.

This is just the reverse of the above, so we need to find:

Angie:  F T
Brenda: T F

The only day that matches either of the two options is Thursday, and it’s option 2. Brenda is the liar.

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How Far Does a Dog Walk?

How far can a blind dog walk into a forest?

Halfway. After he gets halfway, he’s walking out of the forest.

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Cannot Hear or Even See

I cannot hear or even see,
But sense light and sounds there may be,
Sometimes I end up on a hook,
I can be combined with a book.

What am I?

A worm. Worms don’t have eyes or ears, but they can sense light and their bodies can detect vibrations in the ground. Fishers use worms as bait and the term bookwork is used for someone who loves to read.

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Sentca

Four words can be made from the letters below. What are the words?

S E N T C A

1. ENACTS
2. ASCENT
3. STANCE
4. SECANT

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Holds Fast To The Center Of Everything

There is one word that stands the test of time and holds fast to the center of everything. Though everyone will try at least once in their life to move around this word, but in fact, unknowingly, they use it every moment of the day. Young or old, awake or in sleep, human or animal, this word stands fast. It belongs to everyone, to all living things, but no one can master it. The word is?

Gravity.

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Celebrate, Hide Their Shame or Commit Crime

Some use me to celebrate,
Others use me to hide their shame,
Others use me to commit crime.

What am I?

Alcohol. People have a drink to celebrate, but also drink to hide their shame. Lastly, drunk driving is a crime.

A mask is also a valid answer. They can be used to celebrate Halloween or at dress-up parties, a mask can hide your shame and masks are used by thieves.

Update: This one has more valid answers than I thought. Money, drugs and night also work.

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Thin, Bold, Sick And Cold

One thin, one bold,
One sick, one cold.
The earth we span,
To prey upon man.

Who are we?

The Four Horsemen of the Apocalypse.

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From Standard to Sequence

Starting with the word STANDARD, how can you take away two letters and add three digits to make a logical sequence?

Remove the two A’s, leaving: ST ND RD
Add 1, 2, 3 to produce: 1st, 2nd, 3rd.

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