1 2 3 4 5 6 7 8 9 = 100

This equation is incomplete: 1 2 3 4 5 6 7 8 9 = 100

One way to make it accurate is by adding seven plus and minus signs, like so.

1 + 2 + 3 – 4 + 5 + 6 + 78 + 9 = 100

How can you do it using only 3 plus or minus signs?

123 – 45 – 67 + 89 = 100

Posted in Brain Teasers

One Six Seven Nine to Twenty Four

Given the numbers 1, 6, 7 and 9, find an equation that equals 24. You may only use each digit once.

91 – 67 = 24 or
(9 – 6) x (7 + 1) = 3 x 8 = 24 or
6 x √9 + 7 – 1 = 18 + 6 = 24

Posted in Brain Teasers

A Final Screech

I saw a strange creature,
Long, hard, and straight,
Thrusting in a round, dark, opening,
Preparing to discharge its load of lives,
Puffing and squealing noises accompanied it,
Then a final screech as it slowed and stopped.

Note: This may not be appropriate for younger ages.

A subway train.

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Waiting For a Man To Die

I cannot be other than what I am
Until the man who made me dies
Power and glory will fall to me finally
Only when he last closes his eyes.

A prince.

Posted in Riddles

I Cover What Is Real And Hide What Is True

I cover what is real and hide what is true,
But sometimes I bring out the courage in you.

What am I?

A mask. It makes people look different, but can make you feel more powerful than you normally do.

Makeup also works.

Posted in Riddles

Sometimes I’m An Insult

Sometimes I’m an insult,
Sometimes I’m a meal,
But if you see me hanging around,
I hope to change how you feel.

A turkey.

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At Least One is a Boy

A couple has two children. At least one of them is a boy. Assuming the probability of having a boy or girl is 50%, what is the probability that both children are boys?

If you answered 1/2, you’re not without comrades, but the generally accepted answer by statisticians (though not without debate) is 1/3. This is because there are four possible combinations: boy-boy, boy-girl, girl-boy and girl-girl. Since we are told one of the children is a boy (but we don’t know if it’s the first or second child), we can rule out the girl-girl combination, leaving three remaining options. Only one out of 3 is boy-boy, so we get a 1/3 chance.

This is a well-known problem known as the Boy or Girl paradox. The other variation is this brain teaser.

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I Have An Eye But Cannot See

I have an eye but cannot see.
I’m faster than any man alive and have no limbs.

What am I?

A tornado or a hurricane. The calm area in the middle of such a storm is called the eye and wind speeds can reach up to 300 mph in an extreme tornado. Neither one have any arms or legs, but that doesn’t stop them from moving, does it?

Posted in Riddles

A C F H K ?

What is the next letter in this sequence and why? A C F H K _

M. Skip 1 letter then 2 letters, alternating.

Posted in Brain Teasers

The Peace Maker Weapon

What weapon is also a peace maker?

Note: Think homonyms

A knife. It turns things into pieces.

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