It’s the Friday puzzle!

Imagine that you have to make the number 8 from the numbers 4, 7, 6 and 3.  The rules are simple.  You cannot join the numbers together (so 4 and 7 cannot become 47),  have to use each number once and only once, and are only allowed to add, subtract, multiply or divide them.  You might do something like this…..

4+7 = 11

11-6=5

and 5+3=8

So, here is the puzzle….can you make the number 24 with the number 5, 5, 5, and 1 (again, you cannot join the numbers together, have to use each number once and only once, and are only allowed to add, subtract, multiply or divide them)?

As ever, please do NOT post your answer, but feel free to say if you have a solution and how long it took.  Answer on Monday!  have a good weekend.

CGI or genuine?

Lots of people have sent me this great ad…..

Quite frankly, I love it.  What makes it especially interesting is that very little of it is CGI.  So, here is the question – can you identify the CGI?  The answer is out there on You Tube, but I will post a short solution later on.

Big Ben Illusion

This wonderful illusion was created by Frederick Kingdom and colleagues at McGill University, and is one of my favourites. Big Ben appears to tilt more in the photo on the right, but in reality the two photographs are identical….

Any idea why it works?

Can you figure this out?

First, it’s a big day for Simon Singh today!  Simon is a good friend of mine and is currently fighting a libel action brought by the British Chiropractic Association.  His appeal is being heard in the High Court today, and I will be going along to support him.  If you want to support his campaign to keep libel out of science, please sign his petition here.

Second, I recently saw this on you tube….

Any idea what is going on?

It’s the Friday Puzzle!

A ten volume set of books are placed upright, in order, on a shelf (see photograph).  Each book is 4.5 cm thick, and has two covers, each of which are .5 cm thick.  A bookworm starts on page 1 of volume 1 and munches his way in a straight horizontal line through to the last page of the tenth volume.  What distance does the worm travel?

As ever, please do NOT post your solution, but feel free to say whether you have a solution and how long it took you.  Answer on Monday.  Have a great weekend!

I cannot believe this is a static image

Came across the best movement illusion I have ever seen the other day…..

What do you think?  Finding it difficult to believe that it is static?

Update: How odd – some people don’t see it moving at all, and others are blown away by it (including putting it into photoshop to check that it is indeed static!).  Anyone know why there should be such a big difference between people?

Should we bring down the naughty bank?

During the banking crisis, The Royal Bank of Scotland received billions of pounds of public money to stay afloat, such that around 70% of the bank is now owned by the British people.  However, after lots of job cuts, the bank are now saying that they will give around 1.5bn pounds in bonuses to key staff.  Quite a few people think that this is outrageous, including the singer Billy Bragg (who is saying that he will not pay his taxes until the the chancellor of the exchequer curbs the payments), and politician John Prescott (who has started an online petition).

The other day I had an idea for an interesting psychological project.  What would happen if thousands of RBS customers pledge to withdraw their money from the bank on a certain day, unless the bonuses are capped? If enough people were involved, it would probably cause a run on the bank, and so it would be a foolish threat to ignore.  So, here are my questions…
- what do you think of the idea?
- from a psychological perspective, do you think lots of people would join in?
- from a legal perspective, would the scheme break the law?

Can you solve this ghost photo?

I was recently sent an alleged ghost photo, with the following message….

“Hello my name is xx, I recently received this photo from my father which was taken by a friend of his in Jaffna, Sri Lanka where many atrocities have occurred. My father told me about the appearance of what seems to be a lady in the window of the house. I was quite shocked by the photo and wondered if you could shed any light on its authenticity?”

Here is the image

and here is a close-up of the ghost…..

What do you think? A genuine ghost? The full-sized file can be downloaded here (about 1MB)

It’s the Friday Puzzle!

John is sent out to complete a census. He knocks on the door of house number 56 and Jane answers.
Here is the conversation:
John: How many children do you have?
Jane: Three
John: What are their ages?
Jane: I am part of Richard Wiseman’s Friday puzzle and so cannot tell you directly.
John: Oh

Jane: However, I am allowed to tell you that when you multiply their ages together you get 36
John: Oh
Jane: Not only that, see that house directly across the street? Well, the sum of their ages is equal to the number of windows in that house.
John: Oh
Jane: And my oldest really likes bears.
John: Oh
At that point John knows the ages of the three children. What are their ages?

As ever, please do not post a solution, but feel free to say if you solved it and how long it took. Answer on Monday.
Oh, and I will be running a fun session on the science of speed-dating at the Glasgow Science Centre tonight. Details here. Please come along and say hi.

Improve your love life with science

With Valentines Day just around the corner, I thought that it might be a good time to give ten scientifically-supported 59 Second tips to increase your chances of finding and keeping the love of your life…..

The Big Question

Last week I had a conversation with Pete, a dog-owning friend of mine, and we started to create various mind experiments.  Here was our favourite for dog and cat owners out there.

Imagine walking into a room and finding your beloved dog or cat, and a randomly selected two year old child that you have never seen before.  You are presented with a simple choice.  You have to press one of three buttons.  One button will instantly kill your pet.  The second button will instantly kill the child and the third button will instantly kill you. No-one will ever know which button you pressed and there will be no legal ramifications for your choice.  Answer honestly – which button would you press?

Dog and cat owners please vote in the polls below, and feel free to comment.  Everyone else, feel free to comment on what you expect the votes to show, and what they actually seem to show.

Love this illusion soooo much….

This is so simple, but so lovely…..

If you are having trouble seeing how it was created, simply cover up the shadow with your fingers and have another look at the picture.

What do you think? Like?

It’s the Friday Puzzle!

This week I have decided to make the puzzle devil-related.  Imagine running into the devil.

He leans forward and hands you a cloth bag containing a marble, and explains that the marble inside the bag is either black or white.  He then adds a white marble, shakes the bag, and take out a marble at random. It’s white.

Then the devil says ‘What are the odds that the remaining marble is white?  Oh, and if you get it wrong, I get your soul’.

What do you say?

As ever, please do NOT post your answers, but feel free to say if you think you have solved it and how long it took.  Solution on Monday.

Amazing scary 3D illusion

It is turning into a week of devil worshiping and illusions!  @vbloke sent me this great 3D illusion yesterday (you may need to click on it to get it to move)…..

Hope that you enjoy it.  Is your money on the big ugly creature or the kid?

New illusion: Playing in traffic

Well, the pact with the devil post seems to have generated quite a bit of interest!  Great that so many people were happy to hand over their souls – if anyone makes a YouTube video reading out the pact, I will link to it.

Meanwhile, here is a lovely photo illusion that I hadn’t seen before (thank @TheWeeklyExtra)….

What do you think?  Like it?