Page 190 - Ganit Kaushal
P. 190

7                                   Fractions











              7.1 INTRODUCTION                                        Learning Outcomes

              Have you ever shared a pizza with your friends or cut    By the end of this chapter, students will be able to:
              a cake into equal slices for a party? When you divide       • Understand the concept of fractions and recognise
              a whole thing or unit thing into equal parts, you are       them as parts of a whole.
              dealing with fractions! The word fraction is derived        • Identify and differentiate between proper
              from the Latin word “fractus”, which means “broken”         fractions, improper fractions, and mixed numbers.
              and represents a part of a whole. Fractions help us         • Represent fractions on a number line, compare
              understand and represent parts of a whole. Imagine you      and order them.
              have a chocolate bar with 4 pieces, and you ate 1 piece.     • Simplify fractions to their lowest terms.
                       What amount of the chocolate have you eaten?       • Perform basic operations (addition, subtraction,

                       How can you equally distribute three chocolates    etc.) with fractions.
                      among 5 of your friends?                            • Compare and order fractions with the same or
                                                                          different denominators.
                       We will find the answers to all these questions     • Solve problems involving fractions in real life.
                      in this chapter.

              7.2 NOTATION AND MEANING

                                               a
              A fraction is written in the form    or (a/b), and read as ‘a upon b’ or ‘a by b’ where:
                                               b
                 •     ‘a’ is called the Numerator, which tells us how many parts we have.
                 •    ‘b’ is called the Denominator, which tells us how many equal parts make a whole.
                               3
              For example: In  , the numerator is 3, and the denominator is 5. This fraction means we have 3 parts out of
                               5                 1
              5 equal parts that make a whole. In  , the fraction represents half of a whole.
                                                 2
              Equal Shares and Fractional Units

              When one unit is divided into several equal parts, each part is called a fractional unit or a unit fraction.
              For example: If one roti is divided equally between two children, each of them will get
               1  (one half) of the roti. The denominator ‘2’ shows that two equal parts make a whole
               2
              roti, and each child will receive 1 (numerator) part.
              Further, if one roti is equally shared among four children, then each one of them will
                   1
              get    (one fourth) of the roti. The denominator ‘4’ shows that four equal parts make a
                   4
              whole roti, and all the children will have 1 (numerator) part each. (see figure)



              188
   185   186   187   188   189   190   191   192   193   194   195