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A Possible Start
Students need to know how to count. A knowledge of how
counting might of began with tally marks on tally sticks (or walls) may
provide a context.
Tally marks on a stick may have given the earliest way for an individual to
keep track of how many objects possessed or owed.

As long as there is a one-to-one pairing, matching or correspondence between
the tally marks and the objects being tracked, the owner assumes none have been
lost or gained. The tally marks altogether describe and visually count or keep
track of how many objects there
are.
For example, a shepherd may put a tally mark on the tally stick above for each sheep that enters a
pen, and later on verify as the sheep leave the pen that there is still one mark
per sheep. That keeps track of the sheep and ensures none have been lost nor
gain. Births and predators are assumed to account for all changes in the
correspondence. If the tally marks are all alike as they are made, the order in
which sheep leave the pen may be different from then one the entered. All that
is important in concluding that no sheep has been gains or lost is that each
sheep on exit be in one to one correspondence with a tally mark and that all
tally marks are used.
In pure mathematics, two sets are said to be have the same
cardinality (count) or to be equipollent when and only when there is a bijection
or one-toone-correspondence between
them. A bijection in brief is a one to one pairing between the elements
of one set and the elements of the other, so all elements in each set belong along to
one and only one ordered pair. Tracking sheep or marbles with tally
marks on a stick (or paper) provides a bijection between the set of tally
marks and the set of sheep.
The shepherd in keep track of his sheep may have tally marks on several
sticks. In that case, the sheep may be allowed to exit the pen via several
exits. Again as long this exiting gives a one to one pairing between the sheep
and tally marks, the shepherd and we assume none have been lost. The sheep
could be tallied in the first instant by entering the pen via several entrances
or in several groups. It is possible to allow the sheep to enter grouped
in one way and to leave grouped in another way. And if we tallied the
entering and leaving each day using different tally ticks, and different
groupings of the sheep and tally sticks, the different tallies and the
sheep should be in one to one correspondence.
Working Definition of Whole Numbers: A set of tally marks on a
stick gives a whole numbers. So whenever we speak of a whole number, we think of
a set of distinct tally marks on a real or imagined stick.
Assumption
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Tallying or Enumeration Assumption: If a set is tallied (counted) in two different ways, with or
without the use of grouping, the set of tally marks for one way will lie in a
bijection (one to one correspondence) with the marks in the other way.
In other words, we assume any two ways to count the elements of a set
will result in the same number. Later on, we will see that the
equality of two ways to count or measure what is a set or region leads to
properties of arithmetic.
First Tallying or Enumeration Assumption: For a person who can count,
the number of tally marks will be the same regardless of the order in which
the elements of a set are tallied or counted.
Remark for Students of Pure Mathematics:
The following gives a set theoretic justification of the unique tallying
or enumeration principle
Two sets are equipotent when and only when there is a
one-to-one
map from one onto the the other. The latter notion works for both finite and infinite sets as
well.
Theorem: If there is a one-to-one map f of a set
U into a proper subset W of itself then the set is not finite:
Proof If U has N elements and we can find a
one-to-one labeling of those N elements u of U given by a map
c(j): [1,N] -> U. Now d(j) = f(c(j)): [1,N] -> W, a proper
subset of U. Therefore, there is an element s in U not W. Pick such an
s and Put d(N+1) = s. Then the extended map d:
[1,N+1] -> U has a range with N+1 elements in U. The
foregoing shows that if we count N distinct elements in U with the aid
of the mapping c then with the aid of the mapping f, we
can also count N+1 elements as well using another function d. Therefore
for all whole numbers N, there is no bijective map of a range of
whole numbers 1 to N onto U. That is what we mean by saying the set U
is finite.
Contrapostive form of theorem: If U is a finite set
(that is, is in bijective correspondence with a set of whole numbers 1
to N) then then any one-to-one map of U into itself must be
surjective. - if it was not then U would be not finite,
that is infinite.
Unique Tallying Theorem: If P is a finite set
with two maps c: [1,N] --> U and d:[1,M] --> U are
bijections of two possibly different intervals [1,N] and [1,M] then N
= M.
Proof: If N < M then for each j in the interval
[1,M], there is a unique u = d(j) in P and hence a unique
k = c-1(u) = c-1( d(j) ) = f(j) in [1, N]
and hence in [1,M] Therefore f:[1,M] --> [1,M] is an injection.
Yet [1,M] is finite. So the injection must be surjective and hence
N = M. The alternative possibility M < N is
treated similarly. Q.E.D.
Note each of the maps in the Unique Tallying theorem represents a
way to count the number of elements in the set P
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Collecting the tally marks into groups provided a counting or
numeration. Today, we go further. In decimal notation we use digits 1 to 9
to as marks for single object or a group of them, and we use place value to keep
track of how ones, tens, hundreds, thousands etc there are in a count. So
we track groups of power of ten instead of individual elements of a set or sheep
in a pen. None the less, tallying goes on. And when we are counting elements of
a set, we assume the final count or the decimal for it will be independent of
how and in which order the set elements are tallied, counted or numbered.
Decimals
Decimal notation provides a compact form of tally marks for tallying or
counting or describing how many objects there are in a set. The decimal view of
numbers and number theory may be read parallel to the general number theory
pages.
The Start of Number Theory Continues with the following pages
Adding Wholes Multipling
Wholes Distributive
Law Preamble
Distributive Law for Wholes Consequences
More
Consequences
What is a Fraction Compound
Fractions
after this one (and not the next links in top and bottom margins
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Number Theory & Practices
Origins of Counting
A. Start of Number Theory
Section Entrance Origins of Counting Adding Wholes Multipling Wholes Distributive Law Preamble Distributive Law for Wholes Consequences More Consequences What is a Fraction Compound Fractions Extrinsic Numbers Theory
Origins of Counting or Tallying
B. More Number Theory
& Practices
Arithmetic Videos Decimal Place Value Place Value Reinforcement Addition Method Comparison Method Subtraction Methods Multiplication Methods Division Methods Long Division Continued Remainder Arithmetic I Primes & Composites Primes Factorization Theorem GCMs and LCMs from Primes Prime Factorization Aids Prime Factorization Examples Counting Whole No. Factors N-th Roots and Primes Fractions & Decimals Fractions as Decimals 1 = 0.999 Recurring Infinite Decimals Expansion Arith Ratio of Simple Fractions Ratio of Decimal Fractions Unsigned Reals Numbers Signed Coordinates Plane Vectors Horizontal Vectors Adding Vector Multiplies Adding Signed Numbers Multiplying Signed Numbers Distributive Law for Reals Real Numbers Axioms Remainder Arithmetic II
See too complex numbers.
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For
Senior
High School & Calculus Students
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Words to clearly
introduce algebra and variables
have been missing in course design. For people who cannot do
algebra,
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the missing words may
explain or ease their difficulties. Volume 2 ,Three
Skills for Algebra, in Chapters
8 to 14 & 18 etc, puts words before symbols to
providing the missing words in a way that enrich the
comprehension of all. Those words form the middle part of a algebra
(and logic) lessons aimed at helping or improving all
of high school mathematics and also calculus course
design & delivery.
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For Avid Readers in School & Out -
Online Books
1. Elements of
Reason. 1996
1A. Pattern
Based Reason 1995
1B. Math
Curriculum Notes 1996
2. Three
Skills for Algebra 1995
3.Why
Slopes & More.Math
1995
Tour their forewords.
Calculus Prep or Help: See Volumes 2 & 3,
and this bigger
Calculus
Guide. If your
calculus questions is not answered here, submit
it. Over time, that may complete the site development of
calculus.
For Parents: Speaking
Skills, Reading
& Writing,
Preparing for Science, ends,
values and methods for work and study, parent- friendly maths
skill development booklets for ages 4-14.
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Mostly
For High
School
Intro to Solving
Linear Equations
- a different paths for junior and even senior high
school students. Question for Tutors: When do
you use and when you skip the stick diagram method
here?
Fraction
Skills, thought-based development, Ages 10 to 14 may need a
tutor. Students who have to understand in order
to do may like the development in all or part.
For Senior
High School Mathematics & Calculus
5
wordy Logic
Chapters
4 curious Algebra
Chapters
Words before & besides symbols. A Key Algebra
forward & backwards Chapter
First Calculus
Preview (1st intro)
Four Calculus
Chapters
(2nd intro)
Intro to Complex
Numbers (long)
Intro to Mathematical
Induction (romantic & wordy at first)
Tutors & Instructors:
These lessons introduce skills differently Would you
recommend them?
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More Topics
1. Decimal
Arithmetic Reference!
2. Integers
- Intro to Signed No.s
3. Fractions
- fully explained.
4. Fractions
with Units
5. Number
Theory,
6. Solving
Linear Equations
7 Formulas
for- & backwards -
8. Proportionality,
Back- & For-wards.
9. Logic
Chapters:
10. Euclidean-Geometry
11. Slopes
& Equations of Straight Lines. (Take
I. See take II below)
12. Why
Study Slopes.
13. Maps,
Plans, Similarity & Trig,
(Take II included here)
14. Quadratics:
Starter lessons
15. Polynomials:
Starter lessons
16 Why
Factor Polynomials:
17 Functions
- Forwards & Backwards.
18. Exponents,
Radicals & logs.
19. Complex
Numbers before trig (new advance/ starter lesson)
20. DC
Electric
Circuits Etc
21. Real
Analysis
22. The
Olde Complex No, Trig
& Vector Section.
23. More
Calculus Stuff
- written after Volumes 2 and 3.
Level I Material: New Stuff
Time and Date Matters
Level I Arithmetic.
Money Matters
Measurement Matters
Matters of Chance (Risk Control)
Logic
Chapters
(leave what's not clear in Level I to Level II)
Using/Making Maps and Plans.
(A variant of
Maps,
Plans, Similarity & Trig, to
appear here).
For Instructors
-
Education
Essays
(opinions,
possibilities, references)
- Free
Advice and Directions for teaching primary & high school maths
will be given in online meeting place with voice &
whiteboard.
- Math & Logic How-TOs
1. Arithmetic
2. Algebra
3. More Algebra
4. Beginner Geometry
5. More Geometry
6. Calculus
7. Show Work or Logic
These may be too dense for students. Offering ideas to change
education makes this site different. Nothing
ventured, nothing gained. Site material is
mathematically correct, and where not, please report
errors. The two level program POMME in the site
entrance implies multiple paths for instruction. Supporting
those paths in turn implies a clear destination for
site development and perhaps a new name.
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