# What number should be deducted by the numerator and the denominator of the fraction #7/13# to obtain the fraction #1/3#?

##### 2 Answers

8/39

#### Explanation:

Suppose the value that will be deducted from

So,

Solve the equation

Just to show that you get the same answer if you approach it a very slightly different way

Deduct

#### Explanation:

Let the unknown value be represented by

Complying with the wording of the question gives:

But what happens if we change the sign from subtract to add ?

Subtract

Multiply by 1 and you do not change the value. However, 1 comes in many forms.

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Substitute into

Two signs that are not the same give a minus. So

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So it works out correctly whichever way you chose as long as you **'fully'** follow the rules of mathematics.