Riddles and Brain Teasers

Joe and Andrea want to copy three 60-minute cassette tapes. They have a 2-cassette recorder to copy the tapes, allowing them to copy two tapes at a time. Each side takes 30 minutes to be copied, so two tapes can be copied in an hour and the third will take another hour. Andrea bets Joe she can copy all three tapes in 90 minutes. Does she win the bet?

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In the first 30 minutes Andrea copies the A sides of tape 1 and 2.
In the second 30 minutes, she copies tape 1 side B and tape 3 side A (finishing Tape 1).
In the last 30 minutes, she copies tape 2 side B and tape 3 side B.

Posted in Brain Teasers

A Creature, Part Man

This creature, part man and part tree,
hates the termite as much as the flea.
His tracks do not match,
and his limbs may detach,
but he’s not a strange creature to see.

What is it?

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A man with a wooden leg.

Posted in Riddles

Turns Everything Around

What turns everything around but doesn’t move?

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A mirror.

Posted in Riddles

Sometimes I Enter With a Gong

I’m a word, six letters long,
I sometimes enter with a gong.

All in order from A to Z,
I start with the letter B.

What is the word?

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Begins

It has six letters, when a meditation begins they sound the gong, and the letters are in alphabetical order.

Posted in Riddles

Tagged with What am I?

Messy Math

What is the answer to this problem?

48 / 2(9 + 3) = ?

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It depends. Usually, math has one right answer, but in this case, the order of operations can get a little quirky.There are two ways to solve this. First, like so:
48 / 2 × (9 + 3) = ?
48 / 2 × (12) = ?
24 × 12 = 288But another, arguably valid way is:
48 / 2 × (9 + 3) = ?
48 / 2 × (12) = ?
48 / 24 = 2Thanks to KnowYourMeme for providing a great overview on this one. Math StackExchange has more discussion.

It depends. Usually, math has one right answer, but in this case, the order of operations can get a little quirky.

There are two ways to solve this. First, like so:
48 / 2 × (9 + 3) = ?
48 / 2 × (12) = ?
24 × 12 = 288

But another, arguably valid way is:
48 / 2 × (9 + 3) = ?
48 / 2 × (12) = ?
48 / 24 = 2

Thanks to KnowYourMeme for providing a great overview on this one. Math StackExchange has more discussion.

Posted in Brain Teasers

New Door

Rearrange the letters in the words “new door” to make one word.

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“new door” can be rearranged into “one word”

Posted in Brain Teasers

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