NUMBERS
Place Values
Value is the positional value of the digit in the number or where the digit is in the number.
Digits are symbols or characters to represent a number in writing.
Rounding
RULE for rounding off
If number is from 0 and to 4, then DROP or Fall (4) off / let it go
If number is from 5 to 9, then ADD 1 or high 5 --> go higher
Estimate
Rounding numbers is a way of estimating numbers
Dividing Whole Numbers By Tens, Hundreds, And Thousands
When any whole number is DIVIDE by 10, 100, or 1000,
we ‘REMOVE’ or ‘CANCEL’ the corresponding 0s to the number.
Quotient And Remainder
There are special names for each number in a division.
12 ÷ 4 = 3
dividend ÷ divisor = quotient
Factors
Factors are numbers that divide exactly into another number.
The factors of 12, for example, are 1, 2, 3, 4, 6 and 12.
Multiples
Multiples are extended times tables
The multiples of 2 are all the numbers in the 2 times table:
2, 4, 6, 8, 10, ...
Number Operations
Symbol. Some Words/phrases
+ add, sum, plus, total, more than, increased by
- subtract, difference, minus, r less than, decreased
x multiply, product, times
/, ÷ divide, quotient
Order of Operations
First Order. : ( ) Bracket B
Second Order : ÷ X Multiplication, Division DM
Third Order : + - Addition, Subtraction AS
FRACTION
Adding and Subtracting Like Fractions
Add or subtract the numerators
Do not add/subtract the denominator (it indicates the total portion)
Adding and subtracting Unlike Fractions
Method
Step1: Change ALL DENOMINATOTORS to SAME VALUE (equivalent fractions)
Step2: Add or subtract the NUMERATOR
Division Of Fractions
a ÷ c
b d
= a x d
b c
DECIMALS
In the number 17.3, the point separates 17 from the 3.
3 is in the tenth position.
=> 3 of tenths = 3 of 1/10 = 3/10
As a fraction, 17.3 = 17 3/10
Decimal Numbers Multiply By 10s, 100s, 1000s
When a decimal number is MULTIPLY by 10, the decimal value shifts by ONE
PLACE to the RIGHT.
MEASUREMENT
Length
CONVERTING KM/M/CM/MM
1 km = 1000 m
1 m = 100cm,
1 cm = 10 mm
Mass
CONVERTING Kilogram(kg) and Gram(g)
1 kg = 1000 g
kg( / )--->g ( x )
To convert kg to g, multiply the value by 1000
To convert g to kg, divide the value by 1000
Time
Commonly Used Terms
SHAPES
Rectangle and Square
Triangle
Perimeter = adding the three sides
Area of Triangle = ½ x Base x Height
Circle
Angles
Lines
TYPE OF TRIANGLE ANGLES
OTHER ANGLES FORMULAE
QUADRILATERALS
<<< tri ~ 3 , quad ~ 4, cir ~ round >>>
STATISTICS
Drawing and Understanding Graph
Same set of Data in TABLE FORM:
Fruit | Numbers |
Apple | 1 |
Pear | 2 |
Orange | 2 |
Banana | 3 |
Total | 10 |
Average
Formula
Average = Total Amount / Value
Count of shares/items
RATIO
Ratio compares two or more quantities.
Symbol of ratio is :
Ratio of quantity A to quantity B s written as
A : B
** Ratio has no unit of measure
Ratio and Fractions
A fraction is a part of a whole.
PERCENTAGE
"Percent % " means
"per 100" or 'out of 100' or ‘per 100 of the total value’.
-> the first quantity usually represents a part of, or a change in, the second quantity(the whole).
“per 100” =>
60% = 60 / 100
25% = 25 / 100
Percent Formula:
Percent = (Required) Value x 100%
Total Value
GST Formula:
GST = Amount x GST rate
100
SPEED
Distance(D) = Speed (S) x Time (T)
Speed = Distance / Time
Time = Distance / Speed
