Page 180 - Math Smart - 7

CHAPTER 8.2

In this chapter
Equivalent Fractions and
Pupils should be able to:
• simplify fractions by
cancelling common Simplifying Fractions
factors and identify
equivalent fractions
8.2.1 Finding equivalent fractions I

The rectangle is divided into 10 equal parts and
8 parts are shaded.
Look at the shapes below
So, of the rectangle is shaded.
Is there another way we can use fractions to
describe the shaded parts?
If we group 2 units into 1 part, we see that the rectangle has
of
the
5 equal parts and 4 parts are shaded. We say |
rectangle is shaded.
Shape A We say that is equivalent to We write ^ = f.
Q A
and 5 are called equivalent fractions.

We can find equivalent fractions by multiplying or dividing the numerator and
denominator of a fraction by a common factor.

Example 1
Shape B
O Find two fractions that are equivalent to
What fraction of
each shape has been Solution
the
we
both
multiply
shaded? To find an equivalent fraction to | numerator and
denominator by the same number.
Are the two fractions
equivalent? Discuss Here we multiply by 2 and 3 to get two equivalent fractions.
your answers.
X 2 X 3
3 6 3 _9_
4 V^8 4 12
X 2 X 3
Shape A is an octagon.
The words octo, meaning I and ^ are equivalent to
eight, and gonia, meaning
There are many other fractions that are equivalent to |.
angle, come from ancient
Greek. Can you name We find them by multiplying both the numerator and denominator by 4, 5, 6
Shape B?
and so on.

Fractions