Appetizers and Lessons for Mathematics & Reason Français: 26 pages
A 1100+ page site with math-free logic chapters and wordy algebra chapters. For better or best skill development practices, see site chapters and steps.

Logic mastery strengthens comprehension and so improves home, work & study abilities .
Logic 5 Chapters Arithmetic 10 Steps Algebra 12 Starter Steps & 5 Advanced Steps
Work & Study 23 Tips Geometry 15 Steps Calculus 70 Lessons

Ages 15+: Why study slopes Polynomials Quadratics Why factor polynomials Logarithms Functions
What is similarity Euclidean geometry leanly Coordinates + complex no.s Vectors DC Electric Circuits

Ages 14+: Prime factorization Written work formats Decimal place value Extend arithmetic skills orally
What is a variable 5 fraction operations by raising terms Solving Linear Equations: Take I Take II

Online Volumes: 1 - Elements of Reason, 2 - 3 Skills For Algebra, 3 - Why Slopes and
More Math
, 1A - Pattern Based Reason, 1B - Skill Development Principles + Troubles
Forewords + leading chapters give original reasons, still valid, for site content & growth.

Site Review: Mathphobics, this site may ease your fears of the subject, perhaps even help you njoy it. ... unintimidating, sometimes funny and very clear. ... . Read all. Continue with Volume 2, Three Skill for Algebra.

Site Review. Math resources ... span ... arithmetic, logic, algebra, calculus, complex numbers, and Euclidean geometry. Lessons and how-tos .... provide a good foundation ... Read all. See site books as well.

Teachers & Tutors: Site material uniquely explains common troubles in terms of steps too large or missing. Plus, this December 2011, 5-phase framework offers a context for mathematics & logic education. Phases 1 to 3 may focus on skills with actual or potential local value for adult & daily life. College-oriented phases 5 & 4 focus on calculus & preparation for it. Phases 1 to 4 may also serve trades & professions not dependent on calculus.

Location: Site Entrance < Arithmetic and Number Theory Skills << The 20 Times Table

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20 by 20 Multiplication Table

During the school year, practice filling in the 10 or 12 times table at least three times correctly without a calculator. Observe how the numbers increase by a constant amount in each row and in each column.  

* 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
2 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40
3 3 6 9 12 15 18 21 24 27 30 33 36 39 42 45 48 51 54 57 60
4 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 68 72 76 80
5 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
6 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120
7 7 14 21 28 35 42 49 56 63 70 77 84 91 98 105 112 119 126 133 140
8 8 16 24 32 40 48 56 64 72 80 88 96 104 112 120 128 136 144 152 160
9 9 18 27 36 45 54 63 72 81 90 99 108 117 126 135 144 153 162 171 180
10 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
11 11 22 33 44 55 66 77 88 99 110 121 132 143 154 165 176 187 198 209 220
12 12 24 36 48 60 72 84 96 108 120 132 144 156 168 180 192 204 216 228 240
13 13 26 39 52 65 78 91 104 117 130 143 156 169 182 195 208 221 234 247 260
14 14 28 42 56 70 84 98 112 126 140 154 168 182 196 210 224 238 252 266 280
15 15 30 45 60 75 90 105 120 135 150 165 180 195 210 225 240 255 270 285 300
16 16 32 48 64 80 96 112 128 144 160 176 192 208 224 240 256 272 288 304 320
17 17 34 51 68 85 102 119 136 153 170 187 204 221 238 255 272 289 306 323 340
18 18 36 54 72 90 108 126 144 162 180 198 216 234 252 270 288 306 324 342 360
19 19 38 57 76 95 114 133 152 171 190 209 228 247 266 285 304 323 342 361 380
20 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 380 400

Two message to help you build skills and confidence

  • Do you know about the domino effect of mistakes and errors in arithmetic? If not, ask parents, teachers or fellow students to explain what that might be. If yes, if you know about it, then you know about the need to be careful in each arithmetic step you take. The domino effect of errors appears both in and outside of arithmetic. In it, an error in one step likely makes all following steps and any result wrong. Taking care to avoid the domino effects is a must for building skills and confidence in all skill based subjects at home, at work and in school. Good luck.

  • Understanding exactly or precisely what is said or written will avoid confusion when you are following instructions at home, at school and at work. Learning to write and speak exactly or precisely will avoid confusion of others when you explain or give instructions as well. When you are old enough (or now), read the site math free chapter on two logic puzzles. The chapter may help you read, write and speak with precision. That in turn may help you avoid the domino effects in many subjects.

Good Luck.

Arithmetic Steps

Some good practices for skill development in arithmetic appear in site arithmetic and number theory steps. Where these good practices are not best, say so.

  1. Definition of Primes, Simplified : A simpler definition of prime numbers which takes advantage of the 12 times tables to identify small primes upto 13. In particular, a whole number is said to be prime if it is not the product of two smaller whole numbers. With the word smaller in the definition, the whole numbers 11 and 13 are prime because it is not given by a product inside the 10 and 11 times table. [This was the small example given above]

  2. Quick Prime Factorization of Small Whole Numbers: Emphasis of a square or square root rule to provide QUICK prime factorization skills for whole numbers less than 169 = 132. In particular, a whole number less 169 is prime if and only is it is not a multiple of the primes 2, 3, 5, 7 and 11 less than 13. Simple divisibility rules and calculators (an overkill) here may be used to recognize multiples of 2, 3, 5 and 11. Quick prime factorization of whole numbers is a key to exact and efficient fraction practices employed in mathematics from algebra to calculus. There is no escape.

  3. Fraction Operations Explained: A thought-based development of addition, comparison, subtraction, multiplication and division operations starting with simpler cases where operations are easily explained, and continuing on to general cases where all operations are justified by raising terms. In higher mathematics, if not elementary mathematics, comprehension of why methods work is highly valued, it is part of the spirt of mathematics mastery. Understanding how and why operations are justified should move you away from learning by rote. Reference: fraction operations by raising terms

  4. Arithmetic and Fractions With Units: Figuring with denominate numbers, that is multiples of units of measure for physical quantities and units of value for monetary quantities. This practical value for calculations involving speed, rates in general and associated proportionality constants in daily life and also in practical and applied arts and sciences. (In algebra taught by rote, you may see similar figuring with multiples and powers of variables in products and quotients. The path here has more meaning and is very practical)

  5. Oral Dimension of Arithmetic: Verbal description and extension of common practices for finding counts, totals and products by forming and adding or multiplying subcounts, subtotals and subproducts. Here calculation practices are introduced and described orally instead of symbollically, the latter being harder for many to grasp. For many, how to calculate averages and how to calculate perimeters of polygon are best described with words, the use of letter or symbols being to complicated to understand in the first instance. Mastery of common practices for counting, totaling and multiplying do not have to wait for their algebraic description. Instead, the verbal forms can be given. [These arithmetic notes expand on part of the big example given above.]

  6. Place Value Revisited: An exposition of place value in decimals with places before an after the decimal point in groups of three may amuse and inform. In it, students in North America may learn how to read aloud and write on paper the decimal

    6,571,045,375,905,333,034,412.450,033,870

    as 6 sextrillions, 571 quintrillons, 45 quadrillionths, 375 trillionths, 905 billionths, 333 millions, 34 thousands, 421 ones, 450 thousandths, 33 millionths and 870 billionths. In contrast, students elsewhere may use the following "SI" (system international) method how to read aloud and write on paper the decimal form of 6 zettaunits, 571 exaunits, 45 petaunits, 375 teraunits, 905 giga-units, 333 megaunit, 34 kilounits 421 ones, 450 milliunits, 33 microunits and 870 nanounits.

  7. Addition, comparison, subtraction, multiplication and division of decimals: The site development may covered more lightly than presented. The development of place value methods for all but long division is thought-based. Why methods work are both indicated. Long division method is given without justification, but with a method to check results. In all methods, students will meet the domino effects of care and mistakes. Avoiding the latter provides an end, value and tool for skill mastery, an echo of the old fashion idea that figuring well is a sign of practical intelligence.

  8. Signed Numbers: The site description of arithmetic with integers and arithmetic with signed numbers is not bad. The site objective so far has not been to cover everything in mathematics, but to develop and express ideas on how mathematics should be learnt or taught. That being done, a clearer account of arithmetic with signed numbers is due.

  9. More Steps To Elaborate - not in site material: Talk about scientific notation, arithmetic with, and arithmetic with mixed decimals - that is, decimals with multiple places before and after the decimal point. Relate foregoing to fraction skills and practices. Explain the comparison, addition and subtraction of scientific in terms of of finding a common factor or denominator.

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Parents: Help your child or teen learn:

Parent-friendly Work Booklets for ages 3+ to 13 Use these or others to check or build skills.

Mathematics Skills For Ages 3 to 14

Skills with take home value

Basic skills include time-date-calendar Matters; money matters; map, plan and scale diagram matters;counting, measuring and figuring; decision making with logic and likelyhood; being careful and being aware of the domino effect of mistakes; reading and writing with precision.

Is your child able to add, subtract and multiply amounts of money, work with fractions, work with clocks and calendars, work with maps and plans, and measure length, weight-mass and volume? Schools may promote your son or daughter without providing basic skills in reading, writing and arithmetic.

Arithmetic and Number Theory Skills

Algebra Starter Lessons

1 Working With Sets
2 Formula Forward Use - Evaluation
3 Solving Linear Equations - Skip first step with students able to solve 1 eqn in 1 unknown.
4 Computation Rules and Function Notation
5 Real Numbers
6 More Less Greater Than Inequalities and Comparison
7 Axioms Logic and Equivalent Equations
8 Unifying Theme For Algebra
9 Proportionality Backwards and Forwards
10 Examples of Algebraic Reasoning
A Origins of Counting and Figuring Methods
B Real Numbers Extrinsic Development


Site coverage of formuala evaluation format, of computation rules and axioms, and of the forward and backward use of formulas and proportionality relations lessens the amount of natural talent needed to understand and explain algebra.

Geometry - maps plans trigonometry vectors

1 Maps Plans Measurement
2 Euclidean Geometry - Constructions + extras
3 Cartesian and Polar Coordinates
4 Lines and Slopes Take 1
5 What is Similarity
6 Trigonometry first steps
7 Complex Numbers
8 Unit-Circle Trigonometry
9 Lines and Slopes Take 2 with tangent function
10 Intersecting Straight Lines and Transversals
11 Parallel Straight Lines and Transversals
12 Function Translating and Rescaling
13 Vectors
14 Degrees to Radians and Radians to Degrees
15 Arc or Inverse Trigonometric Function

Pre-Teen and young teen mastery of skills and practices which should be common with map-plans-diagrams drawn to scale, contour interpretation included, has actual or potential take-home value for daily- and adult-life in solving routine problems. Elevating some practices to principles, axioms or postualates, provides a base for analytic and Euclidean geometry, an analytic view of similarity, and an efficient mastery of trigonometry and complex numbers. Right triangle trigonometry provide an analytic alternative to solving geometric problems by drawing diagrams to scale.

More Algebra

Natural-Logarithms Exponentials Powers Roots
Five Polynomial Operations
Quadratics Geometrically
Functions
5 Factored Polynomial Sign Analysis Examples
Rewriting algebraic substitution as function substitutions

The first topic leads to a full high school level theory for the forward and backward mastery of growth and decay models and for definition, range and domains of radicals, roots and powers. The next two topics make quadratics and polynomials easier to learn and teach. Site coverage of functions turns vertical and horizontal line rules into computation methods for evaluating functions.

70 Calculus Starter Lessons


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Location: Site Entrance < Arithmetic and Number Theory Skills << The 20 Times Table

[1] [2] [3] [4][5] [6] [7] [8] [9]


Logic-Reason for all
Careful Thinking
Chains of Reason
Mathematical Induction
Responsibility
Bodies-of-Knowledge

Arithmetic - Ages 10+
1. Deciml Place Value - fun
2. Decimals for Tutors
3. Prime Factors - quickly
4. Fractions + Ratios
5. Arith with units - science

Geometry
1 Maps + Plans Use
2 Euclidean Geometry
3 Rct +Polr Coordinates
4 Lines-Slopes [I]
5. What is Similarity
Algebra Starters - the base
1. Better Work Format
2. Solve Linear Eqns
3. Computation Rules
4. Axioms, Item 3 Viewpnt
5. Formulas Backwards
More Algebra
Logarithms-ax & m/nth roots
Five Polynomial Operations
Quadratics Geometrically
Functions || Vectors too
Arith. Skill Check+Answers
Calculus Prep/Preview
What is a Variable
Why study slopes
Why factor polynomials
Complex Numbers
Limits + Continuity

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