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Idiot's Guides: Speed Math

Book Description

The Complete Idiot's GuideĀ® to Speed Math provides easy-to-understand methods, tips, and tricks to do math in one's head, on paper, and on a calculator at a faster rate and with more accuracy for anyone who is intimidated by math and for whom such calculations would otherwise require paper or calculator.

Table of Contents

  1. Cover
  2. Title Page
  3. Copyright Page
  4. Introduction
  5. Part 1: High-Speed Operations
    1. 1 Multiplication
      1. Finger Multiplication
        1. The 2 Times Table
        2. The 3 Times Table
        3. The 4 Times Table
        4. The Universal Times Tables
        5. The 9 Times Table
      2. Special Multiplication by 11
        1. Multiplication of Two-Digit Numbers with 11
        2. Multiplication of Larger Numbers with 11
      3. Below the Base Method
        1. Below Base 10
        2. Below Base 100
      4. Above the Base Method
        1. Above Base 10
        2. Above Base 100
      5. Above and Below the Base Method
        1. Above and Below Base 10
        2. Above and Below Base 100
      6. Multiples and Submultiples
      7. Combined Problems
      8. General Multiplication Using the Vertically and Crosswise Method
        1. Two-Digit by Two-Digit Multiplication
        2. Three-Digit by Three-Digit Multiplication
    2. 2 Addition
      1. Left-to-Right Addition
        1. Two-Digit Numbers
        2. Three-Digit Numbers
        3. Rapid Left-to-Right Columnar Addition
      2. Addition with Numbers Near 10 or a Multiple of 10
      3. Number Splitting
    3. 3 Subtraction
      1. Left-to-Right Subtraction
      2. Subtraction with Numbers Near 10 or a Multiple of 10
      3. Number Splitting
      4. Subtraction with the All from 9 and Last from 10 Method
        1. Subtracting from a Power of 10
        2. Subtracting a Number Ending in Zero from a Power of 10
        3. Subtracting When Neither Number is a Power of 10
        4. Starting the Method Later in the Problem
        5. Ending the Method Earlier in the Problem
    4. 4 Division
      1. Division with the Flag Method
        1. Two-Digit Divisors
        2. Three-Digit Divisors
        3. Four-Digit Divisors
      2. Altered Remainders
        1. Auxiliary Fractions
        2. Type 1: Fractions with a Denominator Ending in 9 or a Series of 9s
        3. Type 2: Fractions with a Denominator Ending in 1 or a Series of 1s
    5. 5 Checking Your Answers with Digit Sums
      1. What Are Digit Sums?
      2. Casting Out Nines
      3. The Nine-Point Circle
      4. Using Digit Sums to Check Your Answers
        1. Checking Addition Answers
        2. Checking Subtraction Answers
        3. Checking Multiplication Answers
        4. Checking Division Answers
  6. Part 2: High-Speed Math Applications
    1. 6 Fractions
      1. Adding Fractions
        1. Fractions with the Same Denominator
        2. Fractions Where One Denominator Is a Factor of the Other
        3. Addition with the Vertically and Crosswise Method
      2. Subtracting Fractions
        1. Fractions with the Same Denominator
        2. Fractions Where One Denominator Is a Factor of the Other
        3. Subtraction with the Vertically and Crosswise Method
      3. Multiplying Fractions
      4. Dividing Fractions
    2. 7 Decimals
      1. The Decimal System and Place Value
      2. Adding Decimal Numbers
      3. Subtracting Decimal Numbers
      4. Multiplying Decimal Numbers
        1. Multiplying by Powers of 10
        2. Multiplying Vertically and Crosswise
      5. Dividing Decimal Numbers
        1. Dividing by Powers of 10
        2. Dividing a Decimal Number by a Whole Number
        3. Dividing a Decimal Number by Another Decimal Number
    3. 8 Percentages
      1. Converting Percentages into Fractions
      2. Converting Fractions into Percentages
      3. Converting Percentages into Decimals
      4. Finding the Percentage of a Given Quantity
        1. Two-Digit Numbers
        2. Three-Digit Numbers
      5. Expressing One Quantity as a Percentage of Another
      6. Approximating Percentages
      7. Percentage Increase or Decrease
        1. Percentage Increase
        2. Percentage Decrease
    4. 9 Divisibility
      1. Divisibility Rules
      2. The Osculation Method
        1. Positive Osculation
        2. Negative Osculation
    5. 10 Squared Numbers
      1. Finding Squares of Numbers Ending in 5
      2. Finding Squares of Numbers Near 50
        1. Numbers Above 50
        2. Numbers Below 50
      3. Using the Duplex to Find the Value of a Squared Number
        1. Two-Digit Squares
        2. Three-Digit Squares
        3. Four-Digit Squares
      4. Combined Operations: Sums of Squares
    6. 11 Cubed Numbers
      1. Finding the Cubes of Two-Digit Numbers
      2. Calculating Cubes Near a Base
        1. When the Number Is Above the Base
        2. When the Number Is Below the Base
    7. 12 Numbers to the Fourth and Fifth Powers
      1. Calculating a Number to the Fourth Power
      2. Calculating a Number to the Fifth Power
    8. 13 Square and Cube Roots
      1. Square Roots of Perfect Squares
      2. Using Duplexes to Find Square Roots
      3. Cube Roots of Perfect Cubes
  7. Appendixes
    1. A Practice Problems
      1. Chapter 1: Multiplication
      2. Chapter 2: Addition
      3. Chapter 3: Subtraction
      4. Chapter 4: Division
      5. Chapter 5: Checking Your Answers with Digit Sums
      6. Chapter 6: Fractions
      7. Chapter 7: Decimals
      8. Chapter 8: Percentages
      9. Chapter 9: Divisibility
      10. Chapter 10: Squared Numbers
      11. Chapter 11: Cubed Numbers
      12. Chapter 12: Numbers to the Fourth and Fifth Powers
      13. Chapter 13: Square and Cube Roots
    2. B Answer Key
      1. Chapter 1: Multiplication
      2. Chapter 2: Addition
      3. Chapter 3: Subtraction
      4. Chapter 4: Division
      5. Chapter 5: Checking Your Answers with Digit Sums
      6. Chapter 6: Fractions
      7. Chapter 7: Decimals
      8. Chapter 8: Percentages
      9. Chapter 9: Divisibility
      10. Chapter 10: Squared Numbers
      11. Chapter 11: Cubed Numbers
      12. Chapter 12: Numbers to the Fourth and Fifth Powers
      13. Chapter 13: Square and Cube Roots
  8. Index
  9. About the Author