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Fractions

Equivalent Fractions

Note that a number of different divisions may have the same answer, for example:

          ,    and so on.

Therefore, the fractions      

= = =

Two fractions are equivalent if one is obtained from the other by multiplying or dividing the same number to both the numerator and the denominator. For example,

is equivalent to both and .

A fraction is irreducible if the numerator and denominator have no common factors (except 1). is irredicible whereas is reducible because 6 and 15 have a common factor of 3 and is reducible because 8 and 20 have a common factor of 4.

In general, if then is equivalent to .

Also, if then is equivalent to .

The following shows an easy method of determining if two fractions are equivalent:

is equivalent to if and only if .

Example

as

as

More Examples (opens in seperate window)

Exercise

Try the following exercises. Each time you click "New Exercise", a new exercise will appear. To answer each exercise, click on either the equality or inequality sign depending on which makes the statement true.

Exercise

Try the following exercise. Click on the sign which makes the statement true. In this exercise, you are asked to determine if the reduced fraction is equivalent to the original fraction.