All the Math You'll Ever Need

Carolyn C. WHEATER taught math and computer technology for more than 40 years to students from preschool through college, including 25 years at the Nightingale-Bamford School in New York City. Now retired, she continues to write about mathematics and test preparation. She is a member of the National Council of Teachers of Mathematics.Steve SLAVIN has a PhD in economics from New York University, and taught economics for 31 years at New York Institute of Technology, Brooklyn College, and New Jersey’s Union County College of Mathematics.

• How to Use This Book ixAcknowledgments  xi1 Getting Started 12 Essential Arithmetic 3Addition 3Multiplication 6Subtraction 9Division 113 Focus on Multiplication 15The Multiplication Table 15Learning the Multiplication Table 16Testing Your Knowledge 18About Long Multiplication 19Practice Exercises with Two Digits 20Multiplying Three Digits 21Four-Digit Multiplication 23Word Problems with Multiplication 254 Focus on Division 29Short Division 29Long Division 33Word Problems with Division 365 Mental Math 41Fast Multiplication 41Fast Division 44How Are You Doing So Far? 46Mental Math Tricks 466 Positive and Negative Numbers 55What Are Negative Numbers? 55Adding Positive and Negative Numbers 56Subtracting Positive and Negative Numbers 57Multiplying Positive and Negative Numbers 58Division with Positive and Negative Numbers 597 Fractions 63Changing the Look of Fractions 63Adding Fractions 66Subtracting Fractions 69Multiplying by Fractions 69Dividing by Fractions 71Cancelling 738 Decimals 77Adding and Subtracting with Decimals 77Multiplying with Decimals 78Dividing with Decimals 809 Converting Fractions and Decimals 83Converting Fractions into Decimals 83Converting Decimals into Fractions 84Simplifying Fractions 86Repeating Decimals 87Non-Terminating Decimals 8810 Ratios and Proportions 91Ratios 91Proportions 9311 Solving Problems 99Words and Fractions 99Word Problems with Money 10212 Area and Perimeter 105Areas of Rectangles 105When We Use Area 108Perimeters of Rectangles 110Areas of Triangles 11313 Circumference and Area 119Circumference of a Circle 119TheAreaofaCircle 12214 Percentages 127Fractions, Decimals, and Percents 127Percent Change 130Fast Percent Change 131Percent Distribution 133Tipping 13515 Solving Simple Equations 139The Care and Treatment of Equations 139Isolating X 140Addition and Subtraction with X 140Multiplication and Division with X 142Fractions and Decimals in Equations 144Negative Numbers 145Multi-Step Equations 14716 Powers and Roots 153Exponents 153Roots 155Advanced Problems 15717 Very Large and Very Small Numbers 161Writing Large Numbers 161Scientific Notation 164Millions, Billions, Trillions, and Beyond 166Multiplying Large Numbers 168Dividing Large Numbers 170Scientific Notation for Very Small Numbers 17118 Algebra Problems 177Age Problems 177Finding the Numbers 181Mixture Problems 18419 Interest Rates 193Simple Interest 193Compound Interest 194A Word on Continuous Compounding 198Doubling Time: The Rule of 70 199Discounting 20120 Rate, Time, and Distance 205The Magic Formula 205The Terms 205Finding Distance 206Finding Rate 208Finding Time 211Rate, Time, and Distance Problems 214Speed Limit Problems 21521 Personal Finance 225Mark-Down Problems 225Sales Tax Problems 228Credit Cards 230Federal Income Tax 232Mortgage Interest and Taxes 23522 Business Math 243Commissions 243Mark-Ups 246Discounting from List Price 248Quantity Discounts 2502/10 n/ 30 252Chain Discounts 256Profit 25723 A Taste of Statistics 267Distributions of Data 267Measures of Center 272Measures of Spread 275Estimating 27924 Review 285Index 311