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Add & Subtract Fractions (Unlike Denominators)

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What you will learn from this videoWhat you will learn
- How to add fractions with UNLIKE denominators.
- How to subtract fractions with UNLIKE denominators.
- This knowledge can help us rollerblade, eat a giant cookie, and even take care of animals!
- Discussion Questions
Before Video
How do you add [ggfrac]3/5[/ggfrac] + [ggfrac]1/5[/ggfrac]?ANSWERYou add the numerators and the denominator stays the same. [ggfrac]3/5[/ggfrac] + [ggfrac]1/5[/ggfrac] = [ggfrac]4/5[/ggfrac].
You subtract the numerators and the denominator stays the same. [ggfrac]5/8[/ggfrac] - [ggfrac]3/8[/ggfrac] = [ggfrac]2/8[/ggfrac].
Multiply the numerator and denominator of the fraction by the same number.
No, because you have multiplied by 1.
Whole number part and fraction part.
After Video
Which part of a fraction tells you the number of equal-sized parts that the whole is broken into? ANSWERThe denominator.
The number of equal-sized pieces being added or subtracted.
For each fraction, multiply the numerator and denominator by a number so that the denominators of both fractions are equal. One possible multiplier is the denominator of the other fraction.
[ggfrac]1/2[/ggfrac].
No; Rafay subtracted the whole number parts but didn't subtract [ggfrac]1/3[/ggfrac] from 5. He should have regrouped to get 4[ggfrac]3/3[/ggfrac] - 3[ggfrac]1/3[/ggfrac] = 1[ggfrac]2/3[/ggfrac].
- Vocabulary
- Numerator DEFINE
In a fraction, the number of equal parts being considered.
- Denominator DEFINE
In a fraction, the number of equal-size parts that a whole has been split into.
- Equivalent Fractions DEFINE
Fractions with different numerators and denominators that name the same number.
- Like Denominator DEFINE
The same denominator.
- Unlike Denominator DEFINE
Different denominators.
- Benchmark Number DEFINE
Numbers such as 0, [ggfrac]1/2[/ggfrac], and 1 that can be used to estimate an answer or evaluate the reasonableness of an answer.
- Mixed Number DEFINE
A number that is written using a whole number and a fraction.
- Numerator DEFINE
- Reading Material
- Practice Word Problems
- Practice Number Problems
- Lesson Plan
- Teacher Guide