Appetizers and Lessons for Mathematics and Reason (www.whyslopes.com)
||Définition d'une variable || Algèbre || Arithmetique || Logique ||La raison basée sur les règles et modelés||

Online Volumes
1,  Elements of Reason.
1A. Pattern Based Reason 
1B. Math Curriculum Notes
2. Three Skills for Algebra
3. Why Slopes & More Math

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1. Help Your Child or Teen Learn 
2. Solving Linear Equations
3. Fractions Ratios Rates Proportions & Units
4. Euclidean Geometry
5. Analytic Geometry/Functions 
6. Number Theory
7. More Calculus
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YOU are better than YOU think. Show yourself  how:  

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Read  logic chapters 1 to 5  in online volume Three Skills for Algebra  for greater skills & confidence in  work 
and study

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 Logic chapters 1 to 5  re- appear not in sequence, as is or longer,  in  Volume 1A,  Pattern Based Reason, Bon Appetite.

Logic Mastery
 Amazing, Amusing, Amorous,  Delicious, Delightful, Edifying, Strengthening Elixir. 
It eases work & learning difficulties Makes the hard easier. Opens eyes. Leads to greater precision.
in reading and
writing

Logic mastery makes the hard, easier. Logic mastery  leads to better, stronger and richer comprehension.  Logic mastery  improves reading and writing.  Logic mastery ease learning difficulties.  Logic mastery gives a headstart.  In sum, logic mastery  will develops critical thinking, improve reading and writing, and give a firmer base for work and studies at many levels. Good luck.


After logic  (a) continue reading Three Skills for Algebra, chapters 8 to 14  and do so alongside site area on solving liinear Equations ; or (b) see this calculus starter lesson and Volume 3, Why Slopes  & More Math, chapters 2 to 6;

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Caution: Site advice is approximately correct, for some circumstances, not all. That leaves room for thought

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What may be learnt and when depends on how skills and concepts are developed. Making the hard easier and clearer will allow earlier & richer development of skills and concepts.


Try the Twiddla Whiteboard. In principle, it  allows to people to draw and chat together online on a copy of this webpage or a clean sheet. The chat may be via text or audio.  Visit www.twiddla.com to set up whiteboards to work with the webpage of your choice.

For online automated help in senior high school maths & calculus, visit  quickmath.com  For Automatic Calculus and Algebra Help with derivatives, integrals, graphs, linear equations, matrix algebra, visit calc101.com  With  overlap, each site quickmath & calc101offers a different range of services, some free, some not, all based on webmathematica. Good luck.

 

8. Addition (and Subtraction) with like Denominators

Instead of counting how much or how is present in terms of whole units we may count in terms of unit fractions. 

Example 1. Counting thirds

2
3
+ 4
3
=  2+4  
3
=  6 
3
= 2

The foregoing says 2 thirds plus 4 thirds (of a unit of measure)  gives six thirds  (of the unit of measure) and the latter is equivalent to 2 (of the unit of measure).

Example 2. Counting Tenths

18
10
+ 15
10
= 18+15  
10
=  33 
10
= 3
10

since 33 = 3*10+3.  The foregoing says 18 tenths plus 15 tenths (of a unit of measure)  gives 33 tenths (of the unit of measure) and the latter can be regrouped in to 3 units (as ten tenths equal 1) plus 3 tenths.

Example 3. Subtracting 12ths.

11
12
- 5
12
= 11-5  
12
=  6 
12
= 6*1 
6*2
= 1
2

since 33 = 3*12+3.  The foregoing says 11 twelfths minus 5 twelfths is 6  twelfths (of a unit of measure). The latter gives a half. The following diagram attempts to illustrate the subtraction and the fact that 6 twelfths is a half. 

 11
12

                     
                     

 6
12

 5
12

 6
12

 6
12

Algebraic Shorthand Pattern or Rule for Addition and Subtraction with like denominators

The general pattern or rule for addition  in terms of shorthand letters is as follows:

A
N
+ B
N
= A+B 
N
    For addition of fractions with the same denominator,
 add numerators and keep the denominator

The general pattern or rule for subtraction  in terms of shorthand letters is as follows:

A
N
- B
N
= A-B 
N
    For subtract of fractions with the same denominator,
 subtract numerators and keep the denominator

 

 

www.whyslopes.com
Fractions, Ratios, Units, Rates & Proportionality

Fraction Starter Lesson
(simplify, multiply, divide & then add or subtract)


Area Map & Intro
Fraction Starter Lesson A
Fraction Starter Lesson B
1 What is a Fraction
2  Multiplication I
3 Multiplication II
4 Multiplication III
5 Equivalent Fractions
6. Mixed Numbers
7  Comparison
8  Addition I
9 Addition II
10 Addition III
11  Multiplication IV
12  Division
13 Two Term Ratios
14 Implied Ratios
15  Multiple Ratios
16  Units in Arithmetic
16 Longer Explanation
16 Change Units
16 Products of Quantities
16. Fractions with Units
16. Division+Reciprocals
17 Proportionality
17 Examples
18 Rates & Slopes EGs
18 Constant Rate
18 Varying Rate
18 Velocity Calc., EGs
18 Changing Units
18 Slopes and Units
18 Slopes, No Units
19 RealPlayer Videos
Links

Arithmetic Videos - Real Player Format

Decimal Addition
Methods
Decimal Subtraction Methods
Decimal Multiplication Methods
Decimal Division
Methods


Fractions
Primes
Greatest Common
Divisors

Least Common Multiples

Square Root
Simplification


Area Content Summary

  1. Fraction Starter Lesson
  2. Real Player Videos on Operations with Primes and Fractions
  3. Continuous Ruler & Line Segment
    model for fractions and operations on fractions - Number Theory Area points to the general model.
  4. Distinction between Ratios and Fractions, a nuance: While binary ratios a:b may be identified with a fraction, triple ratios a:b:c and further multiple ratios cannot.
  5. Saying how to add and subtract like monomials in units and their powers, and saying how multiply and divide like and unlike monomials leads to fraction like expressions involving units and a framework for discussion rates - ratios of quantities - a framework for handling proportionality constants, and framework for carrying units through calculation in quantitative disciplines

Hint: See site area on solving linear equations to strengthen fraction sense and algebra skills together. Good luck.


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