Nine puzzles only smart people understand

On most mornings, most peoples' cognitive functions typically work about as swiftly as a Windows 95 desktop on dial-up.

So what better time to lay before you an array of confidence-crushingly difficult riddles to get those synapses churning back into life.

For a brief moment, you'll be whisked back to that glorious time your hyperactive nephew got a book of riddles for his birthday and spent the entire day firing them off to everyone who could bear to listen.

But this is no child's play - these are some of the hardest puzzles on the known internet.

See if you're able to keep up with the pace (solutions at the bottom):

1. The Palindrome

As we all know, a palindrome is a word that reads the same when spelled backward.

But in what circumstances could the following word be considered a palindrome?

FOOTSTOOL

2. The Chicken Shop

Picture: Oli Scarff/Getty

A fast food restaurant sells chicken in orders of 6, 9, and 20.

What is the largest number of pieces of chicken you cannot order from this restaurant?

3. The Card Trick

I ask Alex to pick any 5 cards out of a deck with no Jokers.

He can inspect then shuffle the deck before picking any five cards. He picks out 5 cards then hands them to me (Peter can't see any of this). I look at the cards and I pick 1 card out and give it back to Alex. I then arrange the other four cards in a special way, and give those 4 cards all face down, and in a neat pile, to Peter.

Peter looks at the 4 cards i gave him, and says out loud which card Alex is holding (suit and number). How?

The solution uses pure logic, not sleight of hand. All Peter needs to know is the order of the cards and what is on their face, nothing more.

4. Just in time...

Picture: Narinda Nanu/Getty

What occurs once in every minute, twice in every moment, yet never in a thousand years?

5. Four Gallons

You have a three gallon and a five gallon measuring device. You wish to measure out four gallons.

6. What am I?

The more of me there is, the less you see.

7. The Lion and the Unicorn

Picture: Martin Schutt/Getty

Alice came across a lion and a unicorn in a forest of forgetfulness. Those two are strange beings. The lion lies every Monday, Tuesday and Wednesday and the other days he speaks the truth. The unicorn lies on Thursdays, Fridays and Saturdays, however the other days of the week he speaks the truth. Lion: Yesterday I was lying. Unicorn: So was I. Which day did they say that?

8. Circles and Lines

Using six contiguous straight lines, connect all of the sixteen circles shown below.

9. Letterati

Which ten letter word in the English language can be typed using only the first row of the computer keyboard?

Given up yet? Scroll down for the answers...

SOLUTIONS

1. Footstool is a palindrome when written in Morse code.

It looks like this:

..-. --- --- - ... - --- --- .-..

2. The answer is 43

After 6 all numbers divisible by 3 can be ordered (because they can all be expressed as a sum of 6s and 9s). After 26, all numbers divisible by three when subtracted by 20 can be obtained. After 46, all numbers divisible by three when subtracted by 40 can be obtained. After 46, all numbers fit into one of these 3 categories, so all numbers can be obtained. 43 is the last number that doesn't fall into one of these categories (44 = 20 + 6 x 4, 45 = 6 x 6 + 9).

3. This one's a bit harder...

Pick out two cards of the same suit. Select a card for Alex where adding a number no greater than six will result in the number of the other card of the same suit. Adding one to the Ace would cycle to the beginning again and result in a Two. For example, if you have a King and a Six of Diamonds, hand the King to Alex. The other three cards will be used to encode a number from 1 through 6. Devise a system with Peter to rank all cards uniquely from 1 to 52 (e.g. the two of hearts is 1, the two of diamonds is fourteen etc...). That will allow you to choose from six combinations, depending on where you put the lowest and highest cards.

4. We weren't even close...

Fill the five gallon container. Pour all but two gallons into the three gallon container. Empty the three gallon container. Put the two remaining gallons from the five gallon container into the three gallon container. Fill the five gallon container one more time. Pour one gallon from the five gallon container by filling the three gallon container. Now the five gallon container contains four gallons.

5. Darkness

6. The letter 'M'

7. Wednesday

As there is no day when both of the beings would be lying, at least one of them must have spoken the truth. They both speak the truth only on Sunday. However, the Lion would then be lying in his statement, so it couldn't be said on Sunday. So exactly one of them lied.

If the Unicorn was honest, then it would have to be Sunday - but previously we proved this wrong. Thus only the Lion spoke the truth when he met Alice on Thursday and spoke with the Unicorn about Wednesday.

8.

9. Typewriter

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