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Upper Primary Mathematics Fractions - Commonwealth of Learning

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Meaning <strong>of</strong> Common <strong>Fractions</strong><br />

To help pupils grasp the concept <strong>of</strong> common fractions, you should expose<br />

pupils to more than one definition. A common fraction may be looked at as a<br />

part <strong>of</strong> a whole, as an expression <strong>of</strong> division, or as a ratio.<br />

Fraction as a part <strong>of</strong> whole: a unit in the form <strong>of</strong> a continuous shape or as a<br />

discrete set is partitioned into equal sized parts.<br />

Fraction as an expression <strong>of</strong> division: if a woman walks 2 km per hour,<br />

5<br />

how many hours will it take to walk 5 km? She takes 5 ÷ 2 or hours.<br />

2<br />

a<br />

A fraction is another way <strong>of</strong> writing a ÷ b.<br />

b<br />

Fraction as an expression <strong>of</strong> ratios: ratios are expressions <strong>of</strong> a relationship<br />

between two quantities. If two out <strong>of</strong> five pupils are boys, then the ratio <strong>of</strong><br />

2<br />

boys to girls can be expressed as 2 to 5 or 2:5 or<br />

5<br />

. The fraction notation <strong>of</strong><br />

ratios is found in proportion.<br />

Fraction Models<br />

Besides the numerical interpretation <strong>of</strong> common fractions, you should use a<br />

variety <strong>of</strong> models such as area, length, and set models. As you go through<br />

this unit, think <strong>of</strong> other model presentations.<br />

Area Models<br />

Area models can be used to demonstrate visually that a fraction is part <strong>of</strong> a<br />

whole. Figure 1.1 illustrates a variety <strong>of</strong> area models.<br />

Circular "pie" pieces Rectangular regions<br />

Geoboards Drawings on grids or dot paper<br />

Pattern blocks Paper folding<br />

Figure 1.1: Area or region models for fractions<br />

Module 2: Unit 1 4<br />

Common <strong>Fractions</strong>

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