Sunday, February 8, 2015

395: One more Solvemymaths area question

What positive and negative shapes (and their dimensions) go into making this yellow figure?
source.

On a side note: isn't it cool that I can say the phrase "negative area" and no one bats an eye?

Saturday, February 7, 2015

394: Spiderbox

You can see that the spider has followed a line around the inside of the box.In the second image, the student has "unfolded" that box and drawn a template.

Is there a way to draw the template so that the spider's path will be one connected path on the unfolded template?




Source.

Friday, February 6, 2015

393: Numbers or Percents




This graph is not distorted, but interpretations of it may jump to wrong conclusions.
  • What incorrect conclusions might be drawn?
  • If a person with a bias against public school funding were to interpret this, how might he do so?
  • Would you fix the graph? If so, how would you change it?
Source, from this page.

Thursday, February 5, 2015

392: Football Field

What shapes (positive or negative) go into creating the track around the football field?
What are their dimensions?

click to embiggen. Right end is photo distortion.

What shapes (positive or negative) go into making the green part inside the track?

If the green is FieldTurf™ at $5/ft² and the red is TopTrax™ at $2/ft², how much money does the Booster Club have to convince the town to put on the ballot?

Everything outside of the track is natural grass.
The preparation cost is $2.25/ft² for the track and the field.

The two gray rectangles on the sidelines are protective felt laid over the track to protect it from football cleats. The light grey on the left is also a protective felt. The two sandy pits at the end of the straightaway are the long jump pits. The narrow stripe in the left end-zone is the pole vault run and the large rectangle in the right end-zone is the high jump run. 

Wednesday, February 4, 2015

391: Adding and Subtracting Shapes

What shapes (positive or negative) go into making the shaded area?
Include important dimensions.

How about here?


What shapes (positive or negative) go into making this figure?

Tuesday, February 3, 2015