“math for the masses”
co-written by Bing Chat (GPT-4)
directed by Dave Auguste
version 2023/06/16 15:51:15 GMT+0100 (BST)

Numbers.

When we learn math, we usually start by learning the names of numbers like “one”, “two”, “three”, and “four”. Then we learn how to match those names with groups of objects that have the same number of things. For example, if we say “one ♠”, we mean “one spade”. If we say “two ♣♣”, we mean “two clubs”. If we say “three ♥♥♥”, we mean “three hearts”. And if we say “four ♦♦♦♦”, we mean “four diamonds”. Finally, we learn how to write the numbers using special symbols like “1” for “one”, “2” for “two”, “3” for “three”, and “4” for “four”.

As we get better at math, we learn how to count bigger and bigger numbers like “ten”, “twenty”, “thirty”, and so on. But sometimes it’s hard to count really big numbers like a hundred or a thousand. That’s why we use special symbols like “100” for one hundred and “1000” for one thousand. These symbols make it easier to do math with really big numbers.

“one • 1”
“ten • • • • • • • • • • 10”
• • • • • • • • • •
• • • • • • • • • •
• • • • • • • • • •
• • • • • • • • • •
• • • • • • • • • •
• • • • • • • • • •
• • • • • • • • • •
• • • • • • • • • •
• • • • • • • • • •
“one-hundred • • • • • • • • • • 100”
“one-thousand ... ?#! 1000”

Please note, it took humans a really long time to figure out how to count numbers and how to write them down. They had to come up with a special system that everyone could use so that they could talk about numbers and do math together. So if you’re learning math and it seems hard, don’t worry! It’s okay to take your time and be patient with yourself.


Number Sense.

At a very basic level, it seems that many animals, including humans, are born with a sense of numbers that allows them to guess how many things are in a group. They also have an ability to tell if two groups have more or less things in them when compared to each other. In math, we can compare numbers to see which one is bigger or smaller or if they are the same. We use special symbols to show this. The symbol “<” means “less-than”, the symbol “>” means “more-than”, and the symbol “=” means “equal-to”.

“is-less-than” < Example : • < •• “is-more-than” > Example : •• > • “is-equal-to” = Example : ••• = •••

So if you see “1 < 2”, it means that “1 is less than 2”.

If you see “2 > 1”, it means that “2 is more than 1”.

And if you see “3 = 3”, it means that “3 is equal to 3”.


Arithmetic.

As we progress in math we learn to add numbers together like :

“1 + 2 = 3”. This is called addition.

But sometimes we need to take numbers away from each other like :

“3 - 2 = 1”. This is called subtraction.

When we add or subtract numbers, we can use a special line with numbers on it called “the number line” to help us understand what’s happening. The number line helps us see how adding and taking away numbers changes them.

-3 -2 -1 0+1 +2 +3 

Examples :
+
Name : “addition symbol” ;
Action : “add” , “plus” ;
Example: “addition pictured as steps toward the right along the number line” ;
• + •• = •••
-3 -2 -1 0+1 +2 +3 -3 -2 -1 0+1 +2 +3 -3 -2 -1 0+1 +2 +3  1 + 2 = 3

Name : “subtraction symbol” or “minus sign” ;
Action : “subtract” , “minus” , “take-away” ;
Example: “subtraction pictured as steps toward the left along the number line” ;
••• − •• = •
-3 -2 -1 0+1 +2 +3 -3 -2 -1 0+1 +2 +3 -3 -2 -1 0+1 +2 +3  3 − 2 = 1


Grids.

To help us understand harder problems, like multiplication, we can use two number lines that cross each other to make a picture with boxes inside it, called “a grid”.

+3 +2 +1 0 −1 −2 −3 −3 −2 −1 +1 +2 +3
Examples :
×
Name : “multiplication symbol” ;
Action : “multiply” , “times” ;
Example: “multiplication pictured as repeated addition along the number line” ;
••• × ••• = •••••••••
-3 -2 -1 0+1 +2 +3 -3 -2 -1 0+1 +2 +3 -3 -2 -1 0+1 +2 +3 -3 -2 -1 0+1 +2 +3 +4 +5 +6 +7 +8 +9  3 × 3 = 9


Example: “outcome of multiplication pictured as a box” ;
• •••
• •••
• × ••• = •••
3 × 3 = 9+3 +2 +1 0 −1 −2 −3 −3 −2 −1 +1 +2 +3 123456789
÷
Name : “division symbol” ;
Action : “divide” ;
Example: “division pictured as repeated subtraction along the number” ;
••••••••• ÷ ••• = •••
-3 -2 -1 0+1 +2 +3 -3 -2 -1 0+1 +2 +3 -3 -2 -1 0+1 +2 +3 -3 -2 -1 0+1 +2 +3 +4 +5 +6 +7 +8 +9  9 ÷ 3 = 3


Example: “outcome of division pictured as equal slices of a box” ;
••• •
••• •
••• ÷ • = •••
9 ÷ 3 = 3+3 +2 +1 0 −1 −2 −3 −3 −2 −1 +1 +2 +3 123

Example: “division pictured as slices through a donut made from concentric circular number-lines” ;
123123456789
Example: “division pictured as parallel slices through a triangle” ;
0+1 +2 +3 0+1 +2 +3 +4 +5 +6 +7 +8 +9 

Fractions and Decimals.

A “fraction” is a special way of writing numbers that shows us how many parts of something we have.

When we multiply a number by a fraction, the effect is like division.


Example: “multiplication of a whole number by a fraction” ;
9 × = 33──32──31──3 0 +1 +2 +3 147258369

9 × =9/1 × 1/3= 9 × 11 × 3= 93=3
Example: “multiplication of a fraction by a fraction” ;
½ × ½ = ¼+1 ½+1 ½ ¼

½ × ½ = 1 × 12 × 2 = 14

When we divide a number by a larger number using a calculator, we get a special kind of fraction called a “decimal”. For example, “5 ÷ 10 = 0.5”.

5 ÷ 10 = 0.50+1 +2 +3 +4 +5 0+1 +2 +3 +4 +5 +6 +7 +8 +9 +100.5

We can use number-lines to convert between fractions and decimals, and percentages as well:

01/601/301/201/151/121/107/602/153/201/611/601/513/607/301/44/1517/603/1019/601/37/2011/3023/602/55/1213/309/207/1529/601/231/608/1511/2017/307/123/537/6019/3013/202/341/607/1043/6011/153/423/3047/604/549/605/617/2013/1553/609/1011/1214/1519/2029/3059/600.000.010.020.030.040.050.060.070.080.090.100.110.120.130.140.150.160.170.180.190.200.210.220.230.240.250.260.270.280.290.300.310.320.330.340.350.360.370.380.390.400.410.420.430.440.450.460.470.480.490.500.510.520.530.540.550.560.570.580.590.600.610.620.630.640.650.660.670.680.690.700.710.720.730.740.750.760.770.780.790.800.810.820.830.840.850.860.870.880.890.900.910.920.930.940.950.960.970.980.99 0% 5%10%15%20%25%30%35%40%45%50%55%60%65%70%75%80%85%90%95% 01/241/121/81/65/241/47/241/33/85/1211/241/213/247/125/82/317/243/419/245/67/811/1223/2410.000.050.100.150.200.250.300.350.400.450.500.550.600.650.700.750.800.850.900.951.000%5%10%15%20%25%30%35%40%45%50%55%60%65%70%75%80%85%90%95%100%

Final Thought...

Question :

Why it is so, in mathematics, that a “positive number” multiplied by a “positive number” produces a “positive number”, a “negative number” multiplied by a “positive number” produces a “negative number”, a “positive number” multiplied by a “negative number” produces a “negative number”, yet a “negative number” multiplied by a “negative number” produces a “positive number”?

Answer :

When we multiply two positive numbers together, we get a positive result because we are adding the same number repeatedly. For example, “2 x 3” means “add 2 three times”, which gives us “6”.

When we multiply a negative number by a positive number, we get a negative result because we are subtracting the same number repeatedly. For example, “-2 x 3” means “subtract 2 three times” which gives us “-6”.

When we multiply a positive number by a negative number, we get a negative result because we are subtracting the same number repeatedly. For example, “2 x -3” means “subtract 3 two times” which gives us “-6”.

Finally, when we multiply two negative numbers together, we get a positive result because we are adding the same number repeatedly but in the opposite direction. For example, “-2 x -3” means “add 2 three times in the opposite direction” which gives us “6”.

I hope this helps!

????...

hmmm...

+1 × +1 = +1-1 × +1 = -1-1 × -1 = +1+1 × -1 = -1



Links.

Rainbow Counters
rainbow_counters.html
“A simple app for teaching addition and subtraction.”

Multiplication Tables
Multiplication_Tables_Two.html
“A colourful table of multiplication tables.”

Counters
counters.html
“An app for teaching addition, subtraction, multiplication and division.”

Zero Times Infinity Is Zero
multiplication_using_grids.html
“An example of how to do multiplication using measurement.”

One Over Zero Is Infinity
division_using_straight_edge_and_compass.html
“An example of how to do division using a straight edge and compass.”

How To Calculate Pi, Using Addition, Subtraction, Multiplication, and Division
How_to_calculate_pi.html
“An example of how to calculate pi using addition, subtraction, multiplication, and division.”

A Beginners Guide To HTML Elements
A_Beginners_Guide_To_HTML_Elements.html
“A application and instruction manual combined, designed to teach programming in JavaScript.”

Regular Expressions in JavaScript
Regular_Expressions_in_JavaScript.html
“A instruction manual and application combined, designed to teach Regular Expressions.”


Videos.