19 September 2011

Mind games 8-answers

Answers to questions 24-25


24. Wacky numbers

The answer is:

7+2+5 = 143547

Why? The secret is to break the large number into groups of two digits. Let’s look at the first example:

5 + 3 + 2 = 15  10  22

15 is 5 multiplied by 3

10 is 5 multiplied by 2

22 is 15 plus 10 minus 3

The other examples show the same pattern. You could write it like this:

A+ B + C = D  E  F


D = A times B

E= A times C

F= D plus E minus B


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25. Rotating snakes

This is an example of the “peripheral drift” or “anomalous motion” illusion. An image with this kind of contrasting arrangement of light and dark colours (or blacks, whites and greys) creates an illusion of motion at the edges of your field of vision, with the “motion” seeming to travel along the shapes in a dark-to-light direction.

At Akiyoshi's illusion pages, you can see many striking illusions in a larger, high-definition format, which makes the effects stronger. Here is a small version of one – using a kind of anomalous motion that makes the image seem to “jiggle” – that Kitaoka designed to advertise the International Congress of Psychology (ICP), to be held in Japan in 2016:

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