Year 9 Mathematics Exam Revision
Percent divided by 100
% to Decimals
= 4b
2a + 2b
Unlike so = 2a + 2b
2a + 2b
= 18p3
6 x p x p x 3p
0 - 90 Degrees
Acute
2dp
Always round to..... in percentages/decimals
2dp
Always round to.....when problem is about money
6.479 - 6.5 (1dp)
Always write write what you're rounding
Brackets, Exponents, Division, Multiplication, Addition, Subtraction
B.E.D.M.A.S
North
Bearing are from the...
Written with three digits
Bearings are always..
Measured in a clockwise direction
Bearings are...
x 1000 x 1000 KL L ML divide 1000 divide 1000
Capacity Unity Conversions
Data that can be PUT INTO GROUPS
Categorical Data
I wonder what is the most COMMON
Categorical Data
A number that is not a prime number (More than 2 factors)
Composite
Data that is MEASURED
Continuous Data
1. Times denominator with whole number 2. Product of that divide by numerator
Converting a mixed number to an improper fraction
1. Divide numerator by denominator 2. Convert remainder to fraction (is the numerator) 3. The denominator is original denominator from improper fraction
Converting an improper fraction to a mixed fraction
Always (x,y)
Coordination
100c to $1 100c to $1.00 (2dp)
Decimals and Money
Decimal x 100
Decimals to %
Date that is COUNTED
Discrete Data
The steeper the gradient the faster it is
Distance/Time Relationships
All the same
Equilateral's sides are..
Price which does not have GST added to it
Exclusive
5(2 + 3) = 5 x 2 + 5 x 3 = 10 + 15 = 25
Expanding Algebra
3(x + 2) + 4(x - 3) = 3x + 6 + 4x - 12 = 7x - 6
Expanding and Simplifying
How many repeats
Exponents show...
4x - 4 = 4(x - 1)
Factorising
few
Factors are...
Multiplying fractions, No big problem Top times top and bottom times bottom Dividing fractions Easy as pie Flip the second and multiply Adding and Subtracting Fractions that you see Match the bottoms perfectly
Fraction Poem
Fraction x 100
Fractions to %
1. Divide numerator with denominator 2. Include remainders (but turn into fraction)
How to turn improper fraction to a whole number
1. Centre - Median 2. Spread - IQR 3. Unusual Value 4. Shape
I Notice Sentence Order
Alphabetical Order
In Algebra, letters are always in...
First
In Algebra, numbers are always..
The price when GST is added
Inclusive
2 Sides the same length
Isosceles' sides have....
Least Common Multiple
LCM
= x5
Law 1 ~ x2 . x3
= a4
Law 2 ~ a6/a2
x 1000 x 100 x10 KM M CM MM divide 1000 divide 100 divide 10
Length Unit Conversions
x 1000 x 1000 x1000 T KG G MG divide 1000 divide 1000 divide 1000
Mass Unit Conversions
Sum of all/number of values (Don't round to whole number!)
Mean
The middle number when the data is ordered
Median
The value occurring most frequently
Mode
= Positive
Negative X Negative
= Negative
Negative X Positive
Coefficient
Number in front of variable is called...
I wonder what the TYPICAL
Numerical Data
90 - 180 Degrees
Obtuse
Added/Subtracted
Only like terms can be...
flour:butter = 1:2
Order is important
change/original x 100
Percentage Change
= Positive
Positive X Positive
Has 2 Factors = One and itself
Prime Numbers
e.g 12:18 = 2:3
Ratios can be simplified
2 Numbers
Ratios must always have...
Angle's on a straight line
Reasoning for straight line
Vertically opposite angles are equal
Reasoning for vertically opposite
Angle's sum of Triangle Base angle's isosceles are equal Angle of equilateral Vertically opposite angles Angle's at a point Angle's on a straight line
Reasons:
180 - 360 Degrees
Reflex Angle
Measure acute angle and subtract by 360 Degrees
Reflex Angles
360 Degrees
Revolution
90 Degrees
Right Angle
3dp
Round to at least...... When decimal is too long
Graph must be equal
Scale = Uniform
All different
Scalene's sides are...
Simplest form
Simplest formAlways let ratios in their....
180 Degrees
Straight Angle
Divide
To find exclusive you...
Multiply
To find inclusive you..
Length x Width
To find the area you have to...
Add all sides
To find the perimeter you have to...
5x = 2x + 24 5x - 2x = 24 3x/3 = 24/3 x = 8
Two Step Equations
Divide
When back is BUYING from you, you....
Multiply
When bank is selling to YOU, you....
Move decimal point forwards
When dividing decimals and there are zeros...
Subtract exponents
When main sign is division...
Add exponents
When main sign is multiplication...
Move decimal point backwards
When multiplying decimals and there are zeros...
10c
When paying cash round to nearest...
0
Whole numbers have...
= 2a
a + a
= 2p
p x 2
