Step-by-Step Computer Generated Practice Test: www.greenemath.com/Pre-Algebra_Practice/Adding_Subtracting_Fractions_Practice/Adding-Subtracting-Fractions-Practice.html Practice Test: www.greenemath.com/Prealgebra/33/AddingFractionsPracticeTest.html

@SSaorise To build your LCM/LCD, you need to factor each number completely. Then you list the largest number of repeats for each prime factor that appears. 12 has two factors of 2, 24 has three factors of two, and 10 only has one factor of two. Since the largest number of repeats is three factors of two, we use three factors of two. Look on my Prealgebra Explained playlist, I have a lesson and practice set on how to find the LCM.

You need to use the largest number of repeats of 2 that appears in any of the factorizations. In the factorization of 8, you get three factors of 2. That's why the LCM(D) gets three 2's put in.

You need to use the largest number of repeats of any prime factor that appears in any of the prime factorizations. So the largest number of repeats of 2 is two occurrences, so we use two factors of two when building the LCM. If you look at all the prime factorizations, 3 only appears as a single factor. Watch my video on finding the LCM.

Thanks for the help my teacher helps other people but not me i really need this stuff

@Greenemath

3 жыл бұрын

Perfect, I'm glad the video was helpful! :)

THANK YOU SO MUCH! Finally... someone was able to fill in the answer to a question I had been having. Suscribed and like. Thanks again :)

@Greenemath

3 жыл бұрын

You are very welcome! :)

That's wonderful news. Congratulations, and I'm so glad I could help you :)

@ricer7688 Can't be at 16:01, but I think you are talking about when I built a factor tree for 20. A factor tree can be started w/ any two factors. The answer will always be the same.

@miashealy16 To simplify a fraction, just factor the numerator and denominator (write as the product of prime factors). Then cancel or cross out any common factors b/w the numerator and denominator. Whatever isn't crossed out is your simplified fraction.

simpler way to find LCD: 2 * 2 * 3 2 * 2 * 2 * 3 2 * 5 2 * 2 * 2 * 3 * 5 = 120 LCD= 120

@Greenemath

3 жыл бұрын

Making a table can be very helpful. Thanks for sharing!

Thank you so much because I was having a quiz on this and I got a A plus thank you so much I applaud you

@Greenemath

3 жыл бұрын

Perfect, thanks for watching :)

thanks cuz I have a math quiz tomorrow and this really helped me cuz I don't understand our lesson XD

@rachelmora08

8 жыл бұрын

Omg me too

@Greenemath

3 жыл бұрын

I'm glad it was helpful! :)

thank you for the website and videos you help me pass my ged :)

@Greenemath

3 жыл бұрын

You are very welcome! 😎

It helps alot😁

@Greenemath

3 жыл бұрын

I'm glad to hear that! :)

Excellent, thank you

@Greenemath

3 жыл бұрын

I'm glad the video was helpful! :)

16:01 why did u 5x4 rather thn 10x2???

@Greenemath

3 жыл бұрын

You can factor 20 as 5 x 4 or 10 x 2, when you build the factor tree, you end up with 5 x 2 x 2. It's the same either way.

im just going to guess on this equation. to much effort!

@Greenemath

3 жыл бұрын

Not really, once you get some practice in, it won't take long at all.

Thank you i will change may brain on you

@Greenemath

3 жыл бұрын

Cool keep up the good work.

Tnx it help me a lot

@Greenemath

3 жыл бұрын

You are very welcome! :)

@brandone859

3 жыл бұрын

GreeneMath.com woahhh , 6 years ago man , im still standing strong in school , thanks for the help u gave a while back !! 😂😂

@Greenemath

3 жыл бұрын

I know, I've been catching up on all the comments. There wasn't a central tab for all comments back then, you had to go to each video. Anyway thanks for appreciating the video. I'm glad you are doing well! :)

why did you only use 2 3s and cross out the rest ?

@Greenemath

4 жыл бұрын

Hi, please indicate the problem number or give a time stamp in the video so I can answer your question.

@tutoringecon ah I see. Thank you.

@Greenemath

3 жыл бұрын

You are welcome!

@ 13:38 why do you just need 3 factors of 2?

@Greenemath

3 жыл бұрын

When we build the LCD, you put the largest number of repeats for any prime factor such as 2, between all prime factorizations. 24 has three, 10 has one, and 12 has two. So the largest number of repeats is three for the prime factor of 2.

How come you used both 2's but not both 3's at 5:45?

@Greenemath

3 жыл бұрын

You use the largest number of repeats between all prime factorizations. With 12 -> 2 x 2 x 3, and with 15 -> 5 x 3, so between the two factorizations, the largest number of repeats of 3 is one, so only one 3 goes in when building your LCD. With 2, it's used twice, so the largest number of repeats is two, so two factors of 2 goes in when building your LCD.

@tutoringecon ahhhhh ok i get it now :) thx man im taking my asvab thursday and uve helped alot :)

@Greenemath

3 жыл бұрын

Glad it was helpful!

how come you needed three 2's at 09.04

@Greenemath

3 жыл бұрын

8 factors into 2 x 2 x 2. When we build the LCD, you put the largest number of repeats for any prime factor such as 2, between all prime factorizations. 8 has three, 10 has one, and 12 has two. So the largest number of repeats is three for the prime factor of 2.

Its indicated operation

@Greenemath

3 жыл бұрын

Yes

Hey thank You for taking the time to do this.. i meant to comment on the other video I have this down pat.. The Long division I had problems with.. Ok so fractions how do you simplify when needed?

@Greenemath

3 жыл бұрын

You would divide both the numerator and denominator by the greatest common factor for the two.

Who is in kumon?

@samehz2011

8 жыл бұрын

Are you

@CryptoSeann

8 жыл бұрын

yes my mom forced me :( u?

@samehz2011

8 жыл бұрын

+SSG777 ProDuctioN same here :( do you like it?

@samehz2011

8 жыл бұрын

+SSG777 ProDuctioN where do you go i go in Canada

@CryptoSeann

7 жыл бұрын

i go in canada

Verry god you will find my number thats it

@Greenemath

3 жыл бұрын

Awesome

but my teacher said cross multiply?

@Greenemath

3 жыл бұрын

You can do that, but you'll have more work when you go to simplify if your denominator is not the LCD.

Why don't help me

@Greenemath

3 жыл бұрын

What problem are you working on?