In a general sense, there is an answer to your question. About 25% of questions are characterized as primarily algebra and 15% as geometry. Other categories such as statistics and probability occur less frequently but are certainly worth studying. And remember that the GMAT adaptive software does not randomly assign question types but ensures that certain things are tested. For example, most students will receive around 4 to 6 geometry questions, (or about 15%).
In studying, I recommend that you follow the order of the quant lessons in a Veritas course. We start with the Math Essentials, it is necessary for you to have the definitions and the calculations down before you move into actual GMAT questions. In this book we use questions that focus directly on the math so that students are ready to perform the necessary calculations when they move to the reasoning portion of "quantitative reasoning."
When you have the essentials down it is important to solidify your Arithmetic. The Arithmetic lesson includes number properties, ratios, percents, uses of prime factors, and other concepts that make up a large portion of the test and the steady execution of which is required for algebra, geometry and word problems.
Next we move to Algebra and subjects like exponents and roots, multiple variables, algebraic number properties, inequalities and functions. Algebra questions are interesting in that - for my money at least - they provide the biggest opportunity to solve a question correctly in about 1 minute if you really see it and to take about 3 minutes to finally end up guessing if you do not see it. That should be reason enough to try to learn the rules and "tricks." Algebra is also crucial to Geometry and word problems.
Next comes geometry, which is limited on the test to a few subjects including lines and angles, triangles, quadrilaterals and other polygons, circles, 3-D figures, and coordinate geometry. Unlike Arithmetic and Algebra geometry does not really building into anything else, but is important on its own.
Word problems should be a priority. We address these in a lesson on problem solving. There are many different types of word problems on the test and each one requires the proper approach and formula. Statistics and probabilities would be next, followed by counting methods.
But above all, BEFORE you really start studying and doing all kinds of problems, develop a good approach to begin each problem solving question and especially each data sufficiency question. And find a way to avoid the errors of misreading, assumptions, and calculation errors! These often account for 2/3 of student errors.
Hope that helps out!!
