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