Addition and Subtration With Fractions

Objective

Know how to add and subtract fractions.

Example

Calculate. Express answers in simplest form

Answer:

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Explanation

You've been through several levels of fractions up to this point. Now, we can finally put it all together to do begin performing calculations. To add or subtract, you must

1. Multiply so both fractions have a common denominator

2. Add or subtract numerators (denominators stay the same)

3. Simplify

1. First, we can't add or subtract two fractions if they have different denominators, so we must find the LCD.

2. Now that we have a common denominator, we can add

3. Now we need to simplify. Reminder, that means

• reduce the fraction part until 1 is the only common denominator

• the fraction can not be improper

It's up to you which part to simplify first. Here, we'll get rid of the improper fraction first

As you can see, our fraction is improper. First, convert it to a mixed number

Now we need to add this new whole number (1) to the whole number we left behind (5)

5 + 1 = 6

All that's left to do now is reduce. We can see that 2 is a common factor. Dividing the numerator and denominator by 2, we get.

Answer:

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Examples

Example 1

1. First, we can't add or subtract two fractions if they have different denominators, so we must find the LCD.

As you can see, our fraction is improper. First, convert it to a mixed number

Now we need to add this new whole number (1) to the whole number we left behind (5)

1 + 2 = 3

All that's left to do now is reduce. But there's nothing to reduce.

Answer:

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Ready?