Grade 9 Maths - Fractions 1
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Transcript of Grade 9 Maths - Fractions 1
Grade 9 Maths
Fractions Review
The next topic in our Number Unit is fractions.
So I can make sure no-one is left behind, let’s start with some basics (quickly), before we move on to our Grade 9 work.
Let’s Review
Fractions are a way to represent a number.
What fractions tell us is how many parts of a whole number we have.
E.g. ½ means we have one part out of the two needed to make a whole.
What Are Fractions?
The top part of the fraction tells us how many parts of the whole we have.
The bottom part of the fraction tells us how many parts make up the whole.
e.g. 1 Numerator (we have one part of the whole)
4 Denominator (four parts make up the whole)
The line – known as the vinculum – means divide
Parts Of A Fraction
In your book, write the following fractions and draw a diagram to show them (e.g. like slices of a pizza).
1 3 6 1 3
3 5 10 4
Draw Your Own Fractions
Solve the following in your book. Draw a diagram if it helps you, otherwise write the question and the answer.
1 – 1/3 = 1 – ½ = 1 – 1/6 = 1/3 + =1 ¼ + = 1
Work It Out
There are 3 types of fractions:
Proper, Improper & Mixed Number
Types of Fractions
A proper fraction has a numerator that is less than the denominator.
Proper Fraction
An improper fraction has a numerator greater than the denominator.
Improper Fraction
A mixed number contains a whole number part and proper fraction part.
Mixed Number
Unit 1 – Types of Fractions Answer the following in your book – write
the question number and your answer as either:
P = Proper Fraction
I – Improper Fraction
MN = Mixed Number
Your Turn
Unit 1 – Types of Fractions
A proper fraction is in its simplest form when its numerator and denominator are as small as possible (this will get you top marks on tests – and it’s easier to imagine simple fractions).
A fraction can be reduced to its simplest form if we divide both the numerator and the denominator by their highest common factor.
Simplifying Fractions
Think to yourself – what is the highest number that can be divided into both the numerator and the denominator?
E.g. 3 ÷3 = 1 6 ÷3 2
Now we have the simplest form of the fraction.
Simplifying Fractions
Unit 6 – Simplifying Fractions Answer the following in your book – write
the question number, the original fraction, what you divide by and your answer:
E.g. 3 ÷3 = 1 6 ÷3 2
Your Turn
Unit 6 – Simplifying Fractions
Book Work Maths Quest 9: Exercise 1D Page 25
Do Question 1 – all problems
Maths Works 9: Exercise 3G Page 51 Do Questions 1-10
In order to solve some problems it will be necessary to change fractions from one type to another.
It becomes especially important when you try to change a fraction to a decimal or percentage.
Converting Fractions
Changing Improper Fractions to Mixed Numbers As we move through this unit, you may be
asked to change an improper fraction to a mixed number to solve a problem.
Here are the steps:1. Divide the numerator by the denominator
and write the answer (this will be the whole number).
2. Write the remainder (if there is one) over the original denominator.
Example:
Changing Improper Fractions to Mixed Numbers
Unit 2 – Changing Improper Fractions to Mixed Numbers.
Answer the following in your book – write the question number, the original fraction, what you divide by and your answer:
E.g. 20 = 20 ÷3 = 6 remainder 2 = 6 2/3 3
Your Turn
Unit 2 – Changing Improper Fractions to Mixed Numbers
Unit 3: Changing Mixed Numbers to Improper Fractions As we move through this unit, you may be
asked to change an mixed number to an improper fraction to solve a problem.
Here are the steps:1. Multiply the whole number by the
denominator and add the numerator.2. Write this answer over the original
denominator.
Unit 3: Changing Mixed Numbers to Improper Fractions
Unit 3 – Changing Mixed Numbers to Improper Fractions.
Answer the following in your book – write the question number, the original fraction, what you multiply by and your answer:
E.g. 2 ¾ = 2 x 4 + 3 = 11= 11/4
Your Turn
Unit 3: Changing Mixed Numbers to Improper Fractions
Book Work Maths Quest 9: Exercise 1D Page 25
Do Question 2 – a-eDo Question3 – a-e
Maths Works 9: Exercise 3C Page 47 Do Questions 1-10 & 26-35
Unit 4: Comparing Fractions
Before we can compare fractions OR add, subtract, multiply or divide fractions, we
must make sure that they have the same denominators.
To do that: 1. Find the lowest common multiple (LCM -the
lowest number that both denominators divide into).
2. Multiply each fraction by the number that will give them the lowest common multiple (LCM).
Unit 4: Comparing Fractions
Unit 4 – Comparing Fractions Find the lowest common multiple for the two
fractions. Multiply each fraction by a number that will give the
lowest common multiple. Write the new fractions. State whether the first fraction is:
> greater than or < less than
Your Turn
Unit 4: Comparing Fractions
Maths Quest 9 Students – Questions 9-20 & 27-32
Maths Works 9 Students – Questions 1-8 & 21-26
Unit 18 - Worksheet
Maths Bingo A Maths Question will appear on the board. The answer will be a number from 1-90. Work out the answer and see if it is a number
on your sheet. If it is, place an X on your sheet over the
number. Once you have five numbers marked with an X,
call “Bingo”. You are the winner! We’ll also play games for first to 10 and first to
15 if there’s time.
Maths Bingo