TJ Prep Problems

TJ Prep practice problems  for our students and readers. The problems provide a very small sampling of what Optimal TJ Prep students work with.

A Medium Geometry Problem for TJ/AOS/Blair Prep. Target Time. 25-55 seconds.

In the figure below two triangles are shown. In triangle ABC, a new triangle is formed by connecting midpoints of sides AB, BC and CA resulting in formation of 4 smaller triangles. Find the ratio of the blue region to the white region. In triangle PQR,  the process used in triangle ABC is repeated successively three times. What is the ratio of the area of the green region to the white region in triangle PQR.

iphone-(null)-0.jpg

A Geometry Question for TJ/SHSAT/AOS/Blair Test Prep (Medium). Target Time 25-40 seconds.

In a far away galaxy, far beyond the reach of our most powerful rockets and weapons exist three planets -- Helios, Feros and Plumbos.   Assume the densities of the three planets are in the ratios of  1:40:60 and their diameters are 2, 4 and 8 million meters. Recall that Mass (commonly referred to as weight) = volume x density. What is the ratio of the volume of the largest plant to the volume of the smallest planet? What is the ratio of the mass of the largest planet to the mass of the smallest planet?