GMAT shortcuts quantitative

I have applied for the GMAT exam and I am weak in quantitative section so can you please tell me some shortcuts to solve the questions of it?

[Shaleen]

Ok, below I am uploading the PDF file of the Quantitative GMAT Math Shortcuts you can feel free to download this

Quantitative Section
Data Sufficiency
Substitution technique for solving math problems
Profit
Discount
Basic Principles of Numbers
Properties of Integers
Averages
Divisibility Rules
Fractions
Decimals
Real Numbers
Ratio and Proportion
Percents
Exponents and Roots
Interest Problems
Sets
Statistics
Probability
Permutation & Combination
Simplifying Algebraic Expressions
Linear Equations
Quadratic Equations
Exponents
Inequalities
Absolute Value
Functions
Time Speed Problems
Work Problems
Mixture Problems
Sets and Venn Diagrams
Parallel and Intersecting Lines
Angles
Triangles
Special Right Triangles
Polygons
Circles
Quadrilaterals
Geometry: Pythagorean Theorem and Triplets
Coordinate Geometry