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

 (Optional Book Orders)
More Site Areas 
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
More Site Areas 
8. Complex Numbers 
9. Qc Maths  Education  
10. Secondary IV(?) maths
11. Real  Analysis 
12. LaTeX2HotEqn:
13. Electric Circuits Etc  
14.  Français
15. Algebra, Odds & Ends, Etc
More Site Areas 
16. Math Education Essays
17. Telling & Working with Time
18. Maps, Plans & Drawings
19. Quantitative Skills for  home, shopping and work 
20. Statistics Useful, or Not.
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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.

Changing and Converting Units

Recall   1 metre = 100 centimetres and  1 decimetre = 10 centimetres.  Here the unlike units metre, centimetre and decimetre are of the same type [L] for length.  So 

 9 metres + 8 decimetres + 3 centimetres 

=  9 x 100 centimetres + 8 x 10 centimetres + 13 centimetres 
= (900 + 80 + 3) centimetres
 = 983 centimetres.

Alternatively  983 centimetres = 98.3 decimetres = 9.83 metres.

In calculations involving lengths, we can replace 

  •  metres by 100 centimetres or 10 decimetres; 
  • decimeters by 0.1 metres or 10 centimetres; and 
  • centimetres by 0.01 metres or 0.1 decimetres.

Here I have use decimal notation for the fractions (1/10) and (1/100) for convenience while typing this page. That is, we could use fraction notation and mixed number notation as well in the foregoing. 

Similarly, we can use the equations

1 minute = 60 seconds, 
1 hour = 60 minutes,
1 day = 24 hours

to go back and forward between unlike units of measurement of time [T]. 

Further examples could follow using units of mass and force or weight.  

Remark - exceptional case: The equality sign is usually has the reflective property that a = b when and only when b = a. Here may read the equality sign to mean the same as or is equivalent to.  For writing

4 pennies + 3  pennies = 7 pennies 

gives and comes from 

7 pennies = 4 pennies + 3  pennies 

But with a change of units we may write 

          3 apples + 4 bananas  = 7 fruits
          ( 3 apples +  4 bananas  yields 7 fruits)

and 

         2 apples + 5 oranges  = 7 fruits

The change of units here does not allow to conclude with out further information that 

7 fruits = or is the same as 3 apples + 4 bananas

because we might also have 

7 fruits = 2 apples + 5 oranges

In discussing fruits of different types,  3 apples + 4 bananas  = 7 fruits is equivalent to 7 fruits = 3 apples + 4 bananas  when and only when we are situation where all individual fruits appearing are considered equivalent when and only when the equality sign means has the same value as and is not be interpreted as yields. 

 

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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