Andrew Geller

Andrew Geller is a top GMAT tutor based out of New York City. Throughout his career he has successfully taught people from many different backgrounds, countries, and starting scores.

In the xy-plane shown, the shaded region consists of all points that lie above the graph of y=x^2 – 4x and below the the x-axis. Does the point (a,b) (not shown) lie in the shaded region if b<0?

In the xy-plane shown, the shaded region consists of all points that lie above the graph of y=x^2 – 4x and below the the x-axis. Does the point (a,b) (not shown) lie in the shaded region if b<0? (1) 0 < a < 4 (2) a^2 – 4a < b A. Statement (1) ALONE is […]

In the xy-plane shown, the shaded region consists of all points that lie above the graph of y=x^2 – 4x and below the the x-axis. Does the point (a,b) (not shown) lie in the shaded region if b<0? Read the Full Article »

When the figure above is cut along the solid lines, folded along the dashed lines, and taped along the solid lines, the result is a model of a geometric solid. This geometric solid consists of 2 pyramids each with a square base that they share. What is the sum of number of edges and number of faces of this geometric solid?

When the figure above is cut along the solid lines, folded along the dashed lines, and taped along the solid lines, the result is a model of a geometric solid. This geometric solid consists of 2 pyramids each with a square base that they share. What is the sum of number of edges and number

When the figure above is cut along the solid lines, folded along the dashed lines, and taped along the solid lines, the result is a model of a geometric solid. This geometric solid consists of 2 pyramids each with a square base that they share. What is the sum of number of edges and number of faces of this geometric solid? Read the Full Article »

In the xy-plane, the origin O is the midpoint of line segment PQ. If the coordinates of P are (r,s), what are the coordinates of Q?

In the xy-plane, the origin O is the midpoint of line segment PQ. If the coordinates of P are (r,s), what are the coordinates of Q? A. (r,s) B. (s,–r) C. (–s,–r) D. (–r,s) E. (–r,–s) Correct Answer: E Full explanation coming soon. Send us a note if you’d like this added to the express

In the xy-plane, the origin O is the midpoint of line segment PQ. If the coordinates of P are (r,s), what are the coordinates of Q? Read the Full Article »

The sum of the integers in list S is the same as the sum of the integers in list T. Does S contain more integers than T?

The sum of the integers in list S is the same as the sum of the integers in list T. Does S contain more integers than T? (1) The average (arithmetic mean) of the integers in S is less than the average of the integers in T. (2) The median of the integers in S

The sum of the integers in list S is the same as the sum of the integers in list T. Does S contain more integers than T? Read the Full Article »