Sunday, May 24, 2015

472: How Many geometry Theorems Are There?

That's pretty much it: How many Geometry Theorems are needed to solve this extended problem?


471: Digits in Fibonacci

We all recognize the Fibonacci Sequence:  1, 1, 2, 3, 5, 8, 13, 21, ...
What is the units digit of the sixty-first Fibonacci number?

Is there a pattern?

470: Poor Alex Bellos

Normally, I'm glad when the nedia talks about math, even if it is simply the latest "Super-Hard problem from Asia that All of Us Stupid American Adults and Brits Won't be Able to Solve but Their 8 Year-old Do Routinely."

Throw in "I gave it to a mathematician and he couldn't solve it either" and you've got an instant viral hit, apparently.

All right, rant over.

What's the error?

Oh, and solve it if you want, too. It's not really that hard.

Further questions:
  • Which blanks CANNOT have a prime number in them?
  • Which blanks COULD have certain prime numbers?
  • Which blanks essentially force this problem to be non-unique?

(answer linked from there)

469: Fix this Graph #ILostCount

This graph needs a lot of work.

What information is being presented?
What is the best way to display this information?
Does this graph rely too much on the reader's knowledge of the city?


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?