Tuesday, May 19, 2015

468: Fields of Green

What is the area of the whole hexagonal shape?

Can your students generalize this result?


Monday, May 18, 2015

467: Squares

Take a square number and multiply by four. Is it guaranteed to still be a square number?

Can we generalize this rule?
Can your students explain why?


Sunday, May 17, 2015

465: Probability Machine

You've all seen Plinko and its variations.  Here's one:

This one has a normal curve drawn on the background. Should it be a normal curve or more triangular like the arrangement of the pins?

Would it still be in this shape if the pins were arranged in a rectangle?

464: Illusion 4 - Side View

How did he pull this off?

Can you sketch this scene from the side?

463: Illusions 3 - Cafe Wall

Here's the original Cafe Wall, after which the Cafe Wall Illusion was named.

What went wrong with this wall? What is it that every single bricklayer and tile-setter knows as Rule #1, to avoid the Cafe Wall Illusion?

462: Illusions 2

How did this artist lay out the guidelines on this flat, concrete floor for this seemingly 3D artwork?

460: Illusions 1

What is the best way to show that the horizontal lines are, in fact, horizontal and parallel?

Why does your brain insist that they are not?