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Upper Primary Mathematics Fractions - Commonwealth of Learning

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Equivalent Fraction Concepts<br />

Pupils should have a sound knowledge <strong>of</strong> equivalent fractions before learning<br />

the four operations on common fractions especially addition and subtraction.<br />

Two fractions are equivalent if they are representations for the same amount.<br />

To acquire the conceptual understanding <strong>of</strong> equivalent fractions pupils should<br />

use models such as area, length, and sets to discover different names for<br />

models <strong>of</strong> fractions.<br />

Practice Activity 7: Area Models<br />

Paper folding can be used to effectively model the concept <strong>of</strong> equivalent<br />

fractions. Fold a sheet <strong>of</strong> paper into halves or thirds. Unfold and colour a<br />

fraction <strong>of</strong> the paper. Write the fraction. Now refold and fold one more time<br />

(Figure 1.7). Before opening, guess how many parts will be in the whole<br />

sheet and how many will be coloured. Open the paper. What fraction names<br />

can be given to the shaded region? Is the name still the same? Why? What<br />

about the amount <strong>of</strong> the shaded part, is it still the same? Why? Record the<br />

equivalent fractions you have generated.<br />

Figure 1.7<br />

Rectangle Slicing: Multiply-by-1-method<br />

We would like you to develop an equivalent fraction algorithm using<br />

rectangle slicing with your pupils.<br />

Put pupils in cooperative learning groups. Give them papers. Have them draw<br />

several equal squares whose sides are 8 cm. Have them shade the same<br />

fraction in several different squares vertically subdividing lines. Next, pupils<br />

slice each rectangle horizontally into different fractional parts, as shown in<br />

Figure 1.8. Help pupils focus on the products involved by having them write<br />

top and bottom numbers as a product in the fraction.<br />

1<br />

Start with each square showing<br />

2<br />

1<br />

2<br />

=<br />

1 × 2<br />

=<br />

2 × 2<br />

2<br />

4<br />

Figure 1.8: A model for the equivalent fractions<br />

Continues on next page<br />

1<br />

2<br />

=<br />

1 × 6<br />

=<br />

6<br />

2 × 6 12<br />

Module 2: Unit 1 10<br />

Common <strong>Fractions</strong>

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