GMAT sample Questions and answers in your inbox is a free service offered by 4GMAT.COM to assist students appearing for GMAT keep a progress check on their GMAT preparation. It helps you to stay sharp. Registered users receive a question by e-mail, free of cost. Detailed explanatory answers and shortcut tips wherever applicable are also provided alongwith the correct answers to each question. Questions are selected from a wide array of topics that typically appear in the GMAT test.
Questions in problem solving and data sufficiency are posted at regular intervals.
A list of all questions that were published as part of this service is provided below. You can browse through the questions on a topic wise basis.
You can register to receive e-mails at
http://groups.yahoo.com/group/4gmat/ or at
http://groups.google.com/group/4gmat/.
Alternatively, you can send a blank email to
4gmat-subscribe@yahoogroups.com.
1. AlgebraIncludes linear equations and word problems that would require framing linear equations to get the solution.
2. Series: Arithmetic and Multiplicative SequencesAP, GP, infinite geometric progressions, summation of series.
3. Arithmetic Mean, Median, Mode, DeviationProblems on simple averages (Arithmetic Mean), Weighted Arithmetic Mean (weighted averages), Median, Mode, Range, Standard Deviation and mixtures and alligations
4. InequalitiesInequalities is considered to be one of the hard topics in the problem solving section. Questions involving algebraic expression, modulus, exponents in inequalities are covered.
5. Data SufficiencyAround a third of the questions in the GMAT math section are data sufficiency questions.
6. GeometryTriangles, angles, quadrilaterals, circles, ellispes.
7. Mensuration - Solid GeometryArea, volume, surface area, of 3d objects such as cuboids, cubes, spheres, hemispheres, cones, cylinders, pyramids and prisms.
8. Number Properties, Theory & Number SystemsLCM, HCF, remainder theory, factorials
9. PercentagesPercentages to fraction or decimal conversion and the reverse. Problems using the concept of percentages.
10. Permutation, Comination and ProbabilityPermutation, combination, sampling with replacement, ordering, re-arrangement of letters of a word, seating arrangements.
11. Profit and LossProfit, loss, expressed as a percentage of cost price, discounts, marked price.
12. Quadratic EquationsNature of roots, real roots, imaginary roots, equal roots, solution to quadratic equations, word problems that require framing quadratic equutions to get the solution.
13. Ratio, Proportion and VarianceStandard problems that involve ratios and proportion, continued proportions, direct and inverse variations.
14. Set TheoryUnion, intersection of sets, disjoint sets, mutually exclusive sets.
15. Simple and Compound InterestSimple interest, compound interest, compounding periods other than on an annual basis.
16. Speed, Time and DistanceAverage speed, relative speed, train problems, boats in streams, races.
17. Work - Time and Pipes - CisternsAmount of work done by a man or woman, time taken by pipes to fill a cistern.
Easy to download Math eBooks on select high scoring topics. Number Theory, Inequalities, Permutation, Probability, Geometry. $6.99 each 
Lesson Books for GMAT Math. Set of 5 books. Formulae, examples, exercises, shortcuts, tests. Rs.1650 within India. US $89 outside India.
Intensive classes for GMAT in Madras, India. 12 weekends, 72 hours. Classes on GMAT Math, Verbal and AWA. Includes study material and Tests. 
Free GMAT Math Problem Solving & DS Practice Questions and Answers