Cross elasticity of demand

Fancy words, huh?
Well, this is what we're working with in the economics class I'm taking, and today we got a task that said "explain this to a five year old" and trust me - that was hard to explain to a five year old!
He was rather bright, but didn't know the fancy words and didn't understand maths so we couldn't explain the equation and how it's calculated.

Anyway, it's rather easy.
Five year old explanation
One store is selling your favorite magazine (Y) and one store is selling your favourite toy (X).
Suddenly people stop buying the magazine, because the toy cost less money than the magazine. So instead of buying one magazine, you can buy two toys.

How it's calculated (10+)
Percentage change in price of X / Percentage change in demand of Y = cross elasticity of demand

Pretty cool and easy, huh?

Just wanted to say how happy I am about the amount of people reading my blog. Sweden, Canada, United States, Russia, Israel, Philippines, Austria, Czech-Republic.. just to mention some. WOW! :)

Peace