Largest Product

Using all the digits from 1 to 7, what two numbers have the largest product? For example, 1234 x 567 = 699678 but you can do much better than that.

742 x 6531 = 4,846,002.

A similar problem can be found in L.A. Graham’s Ingenious Mathematical Problems and Methods with a range of 1 to 9, but the principle remains the same – the numbers with the smallest difference produce the largest product. You start out with the highest two digits, 7 and 6, then attach 5 and 4, putting the smaller of the two digits with the larger number, giving you 74 and 65. The next two highest digits are 3 and 2, giving you 742 and 653. Finally, you add the 1 to the lower number. Page 80 has the details of that solution.

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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.

Posted in Riddles

Animals On the Ark

How many of each animal did Moses take on the ark?

None. Moses didn’t have an ark, Noah did (and yes, he took 2 of each animal).

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Gets Rid of Bad Ones

Gets rid of bad ones,
Short and tall,
Tightens when used
One size fits all.

A noose.

Posted in Riddles

Where None Should Be

One where none should be,
Or maybe where two should be,
Seeking out purity,
In the kings trees.

What am I?

A unicorn

Posted in Riddles

Together As One

I am word with six letters.
My motto is together as one.
If you remove my first and second letters, you can wear me.
If you remove my third letter I can be painful.
If you remove my second, third and sixth letters, Adam & Eve did it.
If you remove my second and third letters, you do this using your mouth.
What am I?

String. A string ties objects together. You wear a ring, a sting hurts, according to the Bible, Adam & Eve committed a sin and you sing with your mouth.

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Against the Rules for You to Play Fair

It’s against the rules for you to play fair,
I always win but you don’t care,
I’ve ruined lives and crushed dreams,
But the allure is too much it seems.

What am I?

A casino. If you use methods to make the odds more fair to you, they kick you out. The house always wins, yet people continue to play. Gambling has ruined countless lives and crushed dreams of making millions, but the hope of winning continues to draw people in.

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The Floating Cork

If a cork is placed into a glass of water, it will almost always drift to the side of the glass. There is one simple way, however, to get the cork to float in the center of the glass. What is it?

Water, the glass, and the cork are all that is required.

The reason that a cork drifts to the side of a glass is that it floats to the highest point. Since water “clings” to the glass, the highest point is around the edge of the water. To get the cork to float in the middle of the glass, all you have to do is fill the glass as much as possible. The water will form a convex shape above the glass, with the highest point at its center. This is where the cork will settle.

Posted in Brain Teasers

More You Take Away, The Bigger I Get

The more you take from me, the bigger I get. What am I?

A hole.

This is quite similar to It Cannot Be Seen and Weighs Nothing.

Posted in Riddles

What Can You Add to One To Make It Go Away?

What can you add to one to make it go away?

The letter g. Then it’s gone.

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