3 - D Geometry and harder AMCs, AIME links

For Mathcounts advanced group -- harder  Mathcounts State/National problem on 3-D geometry.                      

From Mathcounts Mini :

Using Similarity to Solve Geometry Problems

Area and Volume 

Relationship Between A Box's Dimensions, Volume and Surface Area

AMC, AIME videos from AoPS

Harder/Hardest AMC-10, 12 and AIME problems explained by Mrs. Rusczyk

This Week's Work : Week 15 - for Inquisitive Young Mathletes

Part I work for this week:

See if you can write proof to show the exterior angle of any regular convex polygon is \(\frac{360}{n}\).
I'll include that in my blog for better proof.

Polygons Part I : interior angle, exterior angle, sum of all the interior angles in a polygon, how many diagonals
in a polygon

Polygons Part II : reviews and applicable word problems

Interior angles of polygons from "Math Is Fun"

Exterior angles of polygons from "Math Is Fun"

Supplementary angles

Complementary angles

Get an account from Alcumus and choose focus topics on "Polygon Angles" to practice.
Instant feedback is provided. This is by far the best place to learn problem solving, so make the best use of
these wonderful features.

This week's video on math or science : Moebius Transformations Revealed

Part II work online timed test word problems and link to key in the answers will be sent out through e-mail.

Have fun problem solving !!