Previous lesson :
The pupils have previous knowledge of Multiples of numbers and Factors of numbers. They also know how to calculate the lowest common multiple and highest common factor of any given set of numbers
- Meaning Of Fractions
- Types of fractions
- Mixed number
Behavioural objectives :
At the end of the lesson, the pupils should be able to
- Mention various types of fractions
- Say the difference between proper fractions and improper fractions
- Explain mixed numbers
- Convert fractions from improper fractions to mixed number
Instructional Materials :
- Wall charts
- Related Online Video
- Flash Cards
Methods of Teaching :
- Class Discussion
- Group Discussion
- Asking Questions
- Role Modelling
- Role Delegation
Reference Materials :
- Scheme of Work
- Online Information
- 9 Year Basic Education Curriculum
A: Common Fractions
(i) Proper Fractions
(ii) Improper Fractions
(iii) Simple Conversion
A: COMMON FRACTIONS
A fraction is a number which is represented by one integer – the numerator – divided by another integer – the denominator ( or the divisor).
Simply put, a fraction is a part of a whole number. It is not always possible to use whole numbers to describe parts of quantities. It is therefore, important to know that to describe parts of quantities, fraction is used for example.
GENERAL FORM OF A FRACTION
From the explanation given above, we can write fraction in the form
a = the numerator
b= the denominator
Fraction is divided into
1. Common (Vulgar) Fractions
Here, the fraction is written as one number over another .
Numerator is the term given to the number on the top part of a fractions.
Denominator is the term given to the number at the bottom part of a fraction .For example
II. Decimal Fractions
Decimal fractions are simply called decimal numbers. It has numbers to the left and right of a decimal point. See week 5 for detail.
B.Types of Fractions (Common)
Common fractions are grouped under three headings. becausefractions are written as one integer divided by another – a ratio – they are called rational numbers.
Fractions are either proper,improper or mixed.
1.Proper Fractions : This is a common fraction having its numerator less than its denominator. Example
(a) 4/7 (b) 3/5 (c) 2/5 etc
2 Improper Fraction: This is a common fraction having its numerator greater than its denominator .examples.
11/5 (b) 4/3 39/11 (d) etc
3. Mixed Numbers: This type of fraction is in the form of an integer and a fraction. That is it has two parts.
– a whole number, and
– a fraction (usually a proper fraction)
Example is shown in the figure below
From the diagram, we can describe the fraction as 1 ½ oranges
1=whole number part and
½ = fractional part
1.Give five examples each of the types of fraction
2. Using the shapes/figures below, write out the fraction stating whether it is a proper, improper or a mixed fraction.
1. Essential Mathematics for JSS1 by AJS Oluwasanmipg 35 – 36
2. New General Mathematics for JSS1 by M.F Macraeetalpg 29 – 30.
3. Simple Conversions: Conversions can be made from improper fractions to a mixed fraction and vice versa .Lets see some examples.
Express the following improper fractions as mixed fractions
(a) 4/3 (b) 57/10 (c ) 93/20 (d) 113/ 3
(a) = = = 1 + =
Alternatively, divide the numerator by the denominator and express the remainder as the numerator of the fractional part of the mixed fractions. The number of times the numerator can be divided before the remainder is the whole number part.
Hence, 4 = 4 ÷ 3 = 1 remainder 1
= = 1 1/3
(b) 57/10 = = 50/10 + 7/10 = 5 + 7/10 = 57/10
(c )93/20 (d) 113/3
= 80 + 13 = 111 + 2
80 +13 = 111 + 2
20 20 3 3
= 4 + 13/20 = 37+ 2/3
= 4 13/20 = 37 2/3
Conversion from Mixed numbers to Improper Fraction
Let A be the general form of a mixed number, where
A = whole number part
x/y = fractional part.
To convert to improper fraction, the following steps are followed.
1.Multiply the denominator of the fractional part by the whole number
2. Add the numerator of the fractional part to the result in (1) above.
3. Express the result in (2) above as the numerator of the improper fraction with the original denominator of the fractional part as the same denominator.
A = A y + x
Express the following mixed fractions as improper fractions
(a) 5 ½ (b) 3 2/5( c) 7 1/8 (d) 10 1/3
(a) 5 ½ (b) 3 2/5
= 5 x 2 + 1 3 x 5 + 2
= 10 + 1 = 15 + 2
=11/2 = 17/5
( c) 7 1/8 (d ) 10 1/3
= 7 x 8 + 1 = 10 x 3 + 1
= 56 + 1 =
1. Express the following as mixed fractions
(a) 503/10 (b) 113/2
2. Express the following as improper fractions.
(a) 7 ½ (b) 33
READING ASSIGNMENT .
- Essential Mathematics for JSS 1 by AJS Oluwasanmipg
- New General Mathematics for JSS1 by M. F Macrae et al pg
1. Which of the following is not a proper fraction?(a) ¼ (b) ¾ (c )3/2 (d) 5/8
2. Express 3 1/7 as an improper fraction is (a) 11/7 (b)( c) 7/22 (d) 22/ 7
3.What fraction of the figure shown is shaded?(a) 2/11 (b) 3/9 ( c) 8/3 (d) 4/11.
4. Express 99/5 as a mixed fraction (a) 19 4/5 (b) 18 4/5 ( c) 19 5/4 (d) 18 5/4
5.The figures above can best be described as
(a) 2 ½ – mixed numbers
(b) 2 ¾ – proper fraction
(c) 2 ¾ -improper fraction
(d) 2 ¾ -decimal
1. Distinguish clearly the various types of fraction known to you, giving 2 examples each.
2. Express (a) 103/5 as mixed fraction (b) 115 2/5 as improper fraction .
The topic is presented step by step
The class teacher revises the previous topics
He introduces the new topic
The class teacher allows the pupils to give their own examples and he corrects them when the needs arise
The class teacher wraps up or conclude the lesson by giving out short note to summarize the topic that he or she has just taught.
The class teacher also goes round to make sure that the notes are well copied or well written by the pupils.
He or she does the necessary corrections when and where the needs arise.