I need math help

[meems]

Ok, people, I'm exposing my ignorance for all to see

I'm trying to help my son with his math homework. Apparently I do not understand the concept of distributive property. Well, I understand it in a vague sense. I just cannot apply it lol.

How would the following expressions be rewritten using the distributive property?

35 x 27
61 x 19
214 x 73
725 x 48

thx!

[lauren grier]

i just googled. and it hurt my brain severely. me no likey math.

so you basically just need an equation with extra useless steps.. that equals the same on both sides yes?

so like..

ignore. my upside down equation.,

note i hve no idea if that's right.. but that's what i just took from what i read

[scrapperjade]

I have NEVER heard of distributive property before - what grade is he in??

[meems]

he's in 4th.

La, I don't think your equation is right. but then again, what do I know?

[jessica31876]

Me either Jaedyn

Originally Posted by scrapperjade

I have NEVER heard of distributive property before - what grade is he in??

[lauren grier]

that would be because I didn't actually write the correct numbers LMAO.. dear lord.

eta 9x3 = 27... not plus.. LMAO

[scrapperjade]

If what La said is true then:

35 x 27 // (5x7) x (3x9)

61 x 19 // (6x10+1) x (3x6+1)

214 x 73 // (21x10+4) x (9x8+1)

725 x 48 // (29x25) x (6x8)

Maybe?

[newfiemountiewife]

I just asked my kid, he's in 5th, and he never heard of it before. And since he's a math whiz, and I suck...I really can't help you

[lauren grier]

actually....... wth. do i not know the difference btwn plus and multiply at all. I just woke up from a nap ^_^ im editing it out and not trying to re-write it

[lauren grier]

Originally Posted by scrapperjade

If what La said is true then:

35 x 27 // (5x7) x (3x9)

61 x 19 // (6x10+1) x (3x6+1)

214 x 73 // (21x10+4) x (9x8+1)

725 x 48 // (29x25) x (6x8)

Maybe?

yes see. this is what mine would look like if i wasn't asleep.. BUT the thing i found had the left side broken up too /not in the original format... But i dunno if that's necessary?

[aggiefamily]

the definition is a rule that the same product results in multiplication when performed on a set of numbers as when performed on members of the set individually.

So yeah- it is just another way to write the problem by breaking up the factors into their own problems.

[meems]

i found an example

35 x 2 = (30 x 2) + (5 x 2) = 60 + 10 = 70

The example makes sense to me but I'm still stumped.


   
   
          
           

   
          
   
           


[meems]

Originally Posted by aggiefamily

the definition is a rule that the same product results in multiplication when performed on a set of numbers as when performed on members of the set individually.

of course! that is what I was trying to say.

[jessica31876]

so Im just wondering what is the point in this exercise? are they trying to introduce beginning algebra?

[meems]

Originally Posted by jessica31876

so Im just wondering what is the point in this exercise? are they trying to introduce beginning algebra?

i think it was to show them another way multiplying multiple digit numbers. DS said they didn't spend a lot of time on it. I tend to get fixated on minor stuff .

[aggiefamily]

Originally Posted by meems

of course! that is what I was trying to say.

I excelled at 3rd grade math. Then I hit my peak in 4th grade. Anything beyond this and I am no help.

[newfiemountiewife]

Originally Posted by aggiefamily

the definition is a rule that the same product results in multiplication when performed on a set of numbers as when performed on members of the set individually.

So yeah- it is just another way to write the problem by breaking up the factors into their own problems.

[meems]

Originally Posted by aggiefamily

I excelled at 3rd grade math. Then I hit my peak in 4th grade. Anything beyond this and I am no help.

ack, i was hoping you'd come back & post the answers

[meems]

fb to the rescue. one of my friends is 4th grade teacher

30x27 + 5x27
60x19+1x19
70x214+3x214

eta: well, wasn't this fun? I now want to eat an entire bag of chocolate chips.

[aggiefamily]

I am sending you a PM with a link that explains it.

[Sarah8914]

Originally Posted by meems

fb to the rescue. one of my friends is 4th grade teacher

30x27 + 5x27
60x19+1x19
70x214+3x214

eta: well, wasn't this fun? I now want to eat an entire bag of chocolate chips.

I'm a mathed major and I'm a little confused (but it's been years...) to me, distributive would be like this:

27 (30+5) because then you "distribute" the 27 to the 30 and to the 5... but if that's what another 4th grade teacher said, then I'd go with that!

[litabells]

... my head hurts ...

[meems]

Originally Posted by Sarah8914

I'm a mathed major and I'm a little confused (but it's been years...) to me, distributive would be like this:

27 (30+5) because then you "distribute" the 27 to the 30 and to the 5... but if that's what another 4th grade teacher said, then I'd go with that!

i think that's essentially the same thing, isn't it?

[ColleenSwerb]

Originally Posted by meems

i think that's essentially the same thing, isn't it?

It is. I would have put it the same way Sarah did, but yea. It's all the same.

[Sarah8914]

yeah, it is the same... mine was before it was distributed. have fun with that

[AmyM]

I was getting lessons together and saw this in the next couple weeks in Kassi's Math book. I immediately shut the book and went to History. I need to read this again.
She's 4th grade too

[scrapperjade]

Ok seriously people. Do your kids learn advanced algebra in grade 6 and do calculus in Junior year??? LOL!

Maybe it's because I live in a tiny podunk town in the middle of nowhere, but I never even learned this stuff by the time I graduated high school! In grade 3 we were JUST beginning to learn our multiplication, and in grade 4, the most complicated thing we did were beginner fractions & decimals!

[kscwgirl]

where's aaron when you need him?

This whole thread makes my head hurt.

[LeeAndra]

The rainbow-maned unicorn that lives inside my heart just died after I read this thread.

[KristinCB]

Originally Posted by scrapperjade

Ok seriously people. Do your kids learn advanced algebra in grade 6 and do calculus in Junior year??? LOL!

Maybe it's because I live in a tiny podunk town in the middle of nowhere, but I never even learned this stuff by the time I graduated high school! In grade 3 we were JUST beginning to learn our multiplication, and in grade 4, the most complicated thing we did were beginner fractions & decimals!

That is how it was for me growing up too jae.. I have no idea what the curriculum is like for 4th grade here where I am but I have a feeling (99% sure) it isn't this advanced.. I do believe on a whole canada's curriculum is behind what is learned in the states.. I have no idea if that is good or not. LOL

Sometimes I think getting so advanced is just TOO much. Kids still need to be taught common math - accounting etc.. I remember in highschool the higher math class just focused on calculus and geometry and algebra... nothing at all that was actually useful in day to day life :/

I hate math..

[scrapperjade]

I hate math too Kristin!! I hated all the algebra stuff we had to do in high school (which sounds like grade school stuff for US kids!)!

[Kjersti]

Originally Posted by Sarah8914

I'm a mathed major and I'm a little confused (but it's been years...) to me, distributive would be like this:

27 (30+5) because then you "distribute" the 27 to the 30 and to the 5... but if that's what another 4th grade teacher said, then I'd go with that!

Another Math guru here! LOL!! It looks like what your 4th grader is doing is called "mental math". They try to BREAK IT UP into parts that is easier for the kids to add/multiply in their heads.

They say that kids who learn this style of math do really well. It's CRAZY! My daughter is doing it and she's a wiz.....but sometimes I want to scream at her and say.....JUST CARRY THE ONE. She doesn't add, subract, or multiply like I do! ROFL!!!!!

[SirScrapalot]

Ok, so here I am...and this is my two cents (after teaching math in 4th, 6th, and 7th)...When Meems wrote this:


i found an example

35 x 2 = (30 x 2) + (5 x 2) = 60 + 10 = 70

The example makes sense to me but I'm still stumped.

That is what they are talking about. Teaching it in fourth grade isn't as much about starting to teach algebra. Like someone posted earlier, it's about giving another method to reach the answer. While this method may seem foreign to us, math is taught/learned very differently now than it was when we were in school. Research has shown that some children are successful with alternative strategies like this one. After teaching this strategy, it does become a bit easier to use for carrying out problems in my head. With this strategy I don't have to think about "carrying" or where the zero goes in the answer. As long as I know basic facts and addition, I can solve the problem.

Math is so different than when I was in school, but that's not necessarily bad. The reason they probably didn't focus too much on it was b/c it's just another strategy. In my classroom, as well as the other classrooms in my district, it's about finding a strategy that works for you.

That all being said, it is insanely helpful if 4th graders have some idea of this when it comes to algebra.

[newfiemountiewife]

Benjamin is a math whiz, but he does almost everything in his head. Lots of times if you ask him to put his "workings" on paper, he can't. He has this insane way of coming up with the answers. I think it's kind of neat that he can do math in his head, whereas I can barely add 2+2 in my head any more. I didn't mind math when it was the more practical stuff you can actually use, but this kind of stuff is mind boggling to me LOL.

And as a side note, this is how I do math. If I have to add something to 9, let's say 9+5, I always add 10+5 and take away 1. How stupid is that LOL

[livelys]

Just like in the States, here in the UK maths is taught totally differently now to how we were taught as kids.

Have you come across Number Lines, for adding, subtracting etc, too? That's another strategy offered to children over here for working out calculations, as well as partitioning numbers into tens & units, as in this thread.
It seriously hurt my head at first too, but just as Aaron said, for some children who struggle with maths it is a great visual means of getting them to work sums out.

[sprauncey1]

Originally Posted by newfiemountiewife

Benjamin is a math whiz, but he does almost everything in his head. Lots of times if you ask him to put his "workings" on paper, he can't. He has this insane way of coming up with the answers. I think it's kind of neat that he can do math in his head, whereas I can barely add 2+2 in my head any more. I didn't mind math when it was the more practical stuff you can actually use, but this kind of stuff is mind boggling to me LOL.

And as a side note, this is how I do math. If I have to add something to 9, let's say 9+5, I always add 10+5 and take away 1. How stupid is that LOL

Not stupid at all, I do the same thing and I took 4 semesters of college calculus. That question makes my head hurt and I just know my DS is totally going to get it, he just thinks that way. I cannot do math (or spelling) in my head!!!

[ColleenSwerb]

I find it fascinating that things are so different in schools now. I know that SO MANY people out there struuuuuggggggglllllleeeeeeee with math, and I love that they are offering kids a different way of looking at it, instead of THIS IS THE ONLY WAY!

[mummytothree]

I agree that math is so totally different now a days from when we as parents were kids and here is the PROBLEM with that!!! There is very little instruction is class now a days (because of many things...teachers stretched to thin with to many kids, to many state tests {my 3rd grader just had a WHOLE WEEK of PSSA's on top of all her regular work}, trying to shove to much instruction in to little time, different levels of learning in one class {and not enough specialized aids for those kids, so it's left to the teacher}) and a lot of that "slack" is left up to the parents to make up....well if we parents aren't equipped with the tools and knowledge we need to help our kids then our kids get behind and it's that much harder to catch up and it also leaves them feeling helpless when they get to class and are expected to be tested on this!!

When my kids come home with math homework (EVERY NIGHT), I'm almost 37 and I feel so helpless and frustrated...so I can't IMAGINE how my 12 and 8 year old feel!!! I feel like I need to go back to school with them just so I can have a shot in the dark of helping them!!!

And the big kicker.......my kids aren't even allowed to bring their books home because they are school property and might get lost!! So it's often this....parents resorting to googling things until the wee hours of the night and pleading for help on message boards & social networks

And I feel this way and my girls are math wizards and get straight A's...could you imagine how I'd be feeling if they were having trouble!!!

[SirScrapalot]

Speaking from my own experience, this is never the case among the teachers I work with or the teachers my children have had. It is true, yes that teachers are stretched too thin, and yes, testing does take a lot of time...however, I can say that I am consistently checking to make sure my students know what they are doing...after school, over email, and during classes. I'm not trying to say that what you are describing doesn't happen, just that it's not happening everywhere - and that it doesn't apply to every teacher.

New math practices and strategies are based on research for what helps students learn best and what helps them become critical thinkers. Again, not everything is a fit with everyone - but alternate strategies are very useful to a lot of kids.

[fruitysuet]

Crikey, I was totally lost by the posh name given to this type of maths! But now having read Aaron's explanation I have to admit that this IS actually how I work out large sums in my head. Okay I know 35x2 is 70, but for something like 15493 x 3 I would break it down into a combination of smaller sums and then add them together!

In this case I would do

15x3=45x1000=45000
500x3 = 1500 (rounding the 493 up to to 500)
545000+1500=46500

500-493=7, 7x3=21

46500-21=46479

It's a strategy for mental maths I think that most of us DO actually use in real like but don't think about it because it's something we do automatically.

I agree that kids are taught WAY differently than we were and that is a huge struggle for parents at home. I often have to stop my DH from insisting on showing the kids 'the right way to do it' (ie the way we were taught). As my children have moved through school I can see that they do get to that stage eventually, but they progress from a much more visual representation of numbers to start with.

And speaking for myself, these alternative learning strategies are incredibly helpful for my youngest who has learning difficulties.

Oh ... and our school does periodically have parent evenings whereby parents are invited along to workshops to learn about the different teaching methods.

[junebug]

Originally Posted by newfiemountiewife

my thoughts exactly!! math and I do NOT get along. not looking forward to the kids math homework when they are older. Chloe is in first grade right now. addition and subraction i can handle. in fact, she'd better than me i think lol.

[scrapperjade]

Originally Posted by newfiemountiewife

And as a side note, this is how I do math. If I have to add something to 9, let's say 9+5, I always add 10+5 and take away 1. How stupid is that LOL

This is how I do mental math too Jamie! I always round up to 10, then subtract whatever I added. Or instead on adding 1, I "borrow" from the 5... so in my head I do 10+4 instead of 9+5... same answer in the end!

[MamaBee]

I think my brain just exploded... I'm not a math person and I'm really scared by this that this is taught in 4th grade! I sure hope hubby (who's an Engineer and have taken like every math class ever given in college) will be able to help kiddo with the time comes... I agree that it's nice to give alternatives on how to figure out something (don't we all have those memories of coming up with the same answer, but the path was different from the book? Some people think differently... )... my fear is that I sure hope that the kids have a solid foundation on just the basics of adding, subtraction, multiplying and division before the advance or alternative ways are given...