Pre-Algebra
Arithmetic (Spelling)
Spelling of Arithmetic:
A Rat In The House May Eat The Ice-Cream.
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Arithmetic Properties
Commutative Property
The commuting distance is the same in either direction, from home to work or work to home.
The Commutative Property tells us that: a + b = b + a or a × b = b × a
Associative Property
To associate with people is to group up with them.
The Associative Property are about grouping:
(a + b) + c = a + (b + c), or (a × b) × c = a × (b × c)
Distributive Property
To distribute something is to give it to everyone.
The Distributive Property “gives” whatever’s outside the parentheses to everything inside: a (b + c)=ab + ac
Dividing One Fraction With Another
Keep the first fraction, Change the sign from divide to multiply, Flip the last fraction.
Kentucky Chicken Fried
Kangaroo Candy Flowers
Koalas Chasing Ferrets
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Division Algorithm (How To Do Long Division)
Divide - Multiply - Subtract - Compare - Bring Down
Does McDonalds Serve Cheese Burgers?
Does My Sister Cook Bananas?
Divide - Multiply - Subtract -Compare -Remainder
Does McDonald's Sell Cheeseburgers Raw?
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Feet in a Mile
5280 feet = 1 mile
5 Tomatoes
5 to (m)ate oe(s)
5 2 8 0 -- or 5,280 feet in a mile
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Greater Than or Less Than?
< or > ?
Which means greater than? Which means less than? How can you tell?
The alligator has to open its mouth wider for the larger number.
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Metric Unit Prefixes
Metric Units of Measure in Order
* Kilo
* Hecto
* Deca
* Units [meter, liter, gram]
* Deci
* Centi
* Milli
King Hector Doesn't Usually Drink Cold Milk.
King Henry Danced [Merrily / Lazily / Grandly] Drinking Chocolate Milk. For the standard units you can insert [Merrily] for meter, [Lazily] for liter, or [Grandly] for gram.
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Mode & Median
Mode
The mode is the value there are the most of
“MOde” and “MOst” have the same starting 2 letters.
The mode is the Most Occuring Data Entity.
Median
The median splits the data down the middle, like the median strip in a road.
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Which is the Numerator, which is the Denominator?
Think “Notre Dame” (N before D)
nUmerator Up, Denominator Down
Nice Dog (N before D)
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Multiplying Signed Numbers
Analogies can help here.
From sports:
we = pos, win = pos, they = neg, lose = neg, good = pos, bad = neg
we win = good (pos × pos = pos)
we lose = bad (pos × neg = neg)
they win = bad (neg × pos = neg)
they lose = good (neg × neg = pos)
From friendship:
friend = pos, enemy = neg
My friend's friend is my friend (pos × pos = pos)
My friend's enemy is my enemy (pos × neg = neg)
My enemy's friend is my enemy (neg × pos = neg)
My enemy's enemy is my friend (neg× neg = pos)
From life:
good = pos, bad = neg
A good thing happening to a good person is good. (pos × pos = pos)
A good thing happening to a bad person is bad. (pos × neg = neg)
A bad thing happening to a good person is bad. (neg × pos = neg)
A bad thing happening to a bad person is good. (neg× neg = pos)
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Order of Operations
The order of mathematical operations:
* Parentheses
* Exponents
* Multiplication/Division (left to right)
* Addition/Subtraction (left to right).
PEMDAS Mnemonics
1. Please
Excuse
My Dear
Aunt Sally
2. Please
Educate
My Daughters
And Sons
3. Pursuing
Education
Means Dedication
And Study
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Roman numerals
Roman numerals: I =1, V = 5, and X = 10.
I View Xrays.
Roman Numerals: I =1, V = 5, X = 10, L = 50 , C = 100 , D = 500 and M = 1000.
I Viewed Xerxes Loping Carelessly Down Mountains.
I Value Xylophones Like Cows Dig Milk
Roman numerals: L = 50 , C = 100 , D = 500 and M = 1000.
Lucy Can't Drink Milk.
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Use the first letter of each word to help you remember the integers zero through ten.
"Zowie! Only time travelers forge forward." said Sam, entering next Tuesday.
(Thanks Amy for the contribution)
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Speed, Distance and Time
Remember the formula triangle
D = distance traveled
S = Average speed
T = Time taken
You can use the formula triangle in the following way:
If you need to find D, cover up D in the triangle and you get S × T
If you need to find S, cover up S in the triangle and you get
If you need to find T, cover up T in the triangle and you get
