Fractions Basics - Math Lesson - Free Educational videos for Students in K-12

Fractions Basics - Math Lesson - By tecmath

Transcript


00:0-1	today in this video we're going to be doing is
00:02	we're going to do something to look at the basics
00:03	of fractions , fractions numbers which are used to describe
00:08	parts of a whole and you'll often see them written
00:11	as follows . I'll write one down right now ,
00:14	three quarters a common fraction . But I'll just go
00:17	through to explain the different parts of the different names
00:20	of what we have when we talk about fractions .
00:22	So first off we have the number up the top
00:25	here and the top number is called the numerator and
00:29	I'll just write that down . Okay , so this
00:31	is called the numerator . The bottom number here is
00:35	called the denominator , the deer nominator . And you'll
00:40	quite often hear people refer to the lowest common denominator
00:43	and things like this . Okay , so we often
00:46	just think of this as top number and bottom number
00:48	, but it's a numerator and the denominator , the
00:51	other part of a fraction that we have here is
00:54	this part here , which is this line here .
00:56	Okay . And this line is called the vin column
01:00	and I know I am going to say that incorrectly
01:02	, the vin column . So just say it twice
01:05	just to really reinforce the incorrect way of probably saying
01:08	it . So often when I think about this middle
01:11	part here , I think about this being divide .
01:13	So I'll show you what I really mean by this
01:15	. When I talk about this , When I think
01:17	about fractions , I think about them being either three
01:20	parts of four or three out of four . But
01:23	if I'm thinking about this sometimes the numbers , I
01:24	also think this has three divided by four and I
01:27	think that's a great way to think about it as
01:29	well . And that helps you if you get stuck
01:32	on fractions because you can work out what the decimal
01:35	of these are just by going three divided by four
01:38	, which is equal to 0.75 . Then further from
01:42	this you can see the relationship to percentage because this
01:45	number is out of one but if we multiply by
01:48	100 just to make it a little bit nicer .
01:49	We end up with the percentage which is 75 percent
01:54	. So what types of fractions do we have now
01:57	? I guess the proper fraction is what you think
01:59	of as a normal fraction where we have ? Our
02:01	denominator is bigger than our numerator . So the number
02:04	we have before three quarters was an example of a
02:08	proper fraction . Half would be an example of a
02:11	proper fraction or say something like three fits . Okay
02:15	, these are all examples of proper fractions are denominator
02:19	is bigger than our numerator . How we have another
02:21	type of fraction which is important to know which is
02:23	called an improper fraction . So improper fractions as opposed
02:27	to proper fractions are fractions where the numerator is bigger
02:32	, Then the denominator an example for this might be
02:34	4/3 . Okay , four out of three . And
02:38	you might think that's a bit counterintuitive . How can
02:39	you have a bigger number out of a smaller number
02:42	and we'll have a look at that in a little
02:44	bit later . Okay ? Or you might have something
02:46	like five out of two . Any time that you
02:49	have this numerator bigger than the denominator , you have
02:53	yourself an improper fraction . Now we can change an
02:56	improper fraction too . What's known as a mixed number
03:01	. So this leads us to another type of fraction
03:03	which is a mixed number . A mixed number is
03:06	where you have a mixture between whole numbers and fractions
03:09	. Okay , so four out of three as a
03:11	mixed number . I'm gonna show you at a different
03:13	stage how to work this out . And they're pretty
03:14	easy . Would be written as one and one third
03:18	or 5/2 Could be written as 2.5 . Okay .
03:23	We have an improper fraction which can be converted across
03:27	to a mixed number . So just to explain all
03:30	those different ideas we've gone through and how they relate
03:33	to one another . What about I'll show you on
03:35	a number line . So we got this number line
03:37	and it's going along it's gonna start at zero .
03:40	We go along one part We go along another 2
03:44	2 . We don't need to actually go any further
03:47	to show you what I want to show you here
03:48	. So say let's consider the fraction three quarters .
03:52	Now at the moment this is in a proper fraction
03:54	form . Okay , our denominator is bigger than our
03:57	numerator . So let's actually put this on the number
04:00	line . How do we go about doing this between
04:03	10 here , divide up this many times the amount
04:06	which is the denominator . So we're going to break
04:08	up between one and zero here . Four times four
04:11	. Equal parts 1234 We can keep going and keep
04:15	doing it here as well . 1234 So we can
04:17	do now is we can go through and start putting
04:19	fractions along our number line here . All related to
04:22	quarters . We could go along one part And we
04:24	have gone one out of four . We go along
04:27	to party and we're going to out of four .
04:30	We go along another one and we've gone three parts
04:32	out of four and you're gonna see this is the
04:34	one we wanted to put on . Gonna rub that
04:36	out because I'm going to keep going to this idea
04:38	here , we've gone four out of four . And
04:41	as I said before you get to go , hey
04:42	, that's 14 out of four is equal to 14
04:45	divided by four is equal to one . Like we
04:48	said before , we have five out of four .
04:50	We can keep going . We have six out of
04:53	four . We have seven out of four . We
04:56	could go eight out of four . Once again ,
04:57	eight divided by four is equal to two . All
05:01	right , So what have we got so far ?
05:03	You can see what we have here is a whole
05:05	bunch of proper fractions . We go here and we
05:10	have a whole bunch of improper fractions . So what
05:12	we could also do is we could change all these
05:15	guys here across to mixed numbers . Okay ? Because
05:19	five divided by four is one and one left over
05:23	one out of four . Okay , This is one
05:25	plus one quarter . Okay , So one and a
05:27	quarter . This is one and two quarters , this
05:32	is one and three quarters . So we'll put that
05:34	one in there and I'll put this one in here
05:36	because that fits as well . This is one and
05:38	three quarters and seven divided by four is one with
05:41	three left over 3/4 . That's pretty all right ,
05:44	not too bad . Just leave that last thing I
05:47	want to explain which is I guess equivalent fractions .
05:51	Now , what we also could have done is we
05:52	could have got our number line here instead of breaking
05:55	up before I could have considered halves . Now I'm
05:59	going to leave this all up here because I just
06:01	want to use it to explain something and that is
06:03	equivalent fractions . So if I was to break this
06:06	up into halves , let's start with my zero .
06:08	And I would have broken it up like this .
06:09	Okay , I'll be breaking it up into halves .
06:12	Okay , one there has been halved into two equal
06:15	parts and this part here has been hardening technical parts
06:18	. Now if I was going up like this ,
06:20	what you'd see is I'd go up one at a
06:22	two , I would have gone up to about 2-3
06:25	out of 24 at it too . But it's just
06:27	these parts here that I want to show you what
06:30	we have is equivalent fractions here . two is twice
06:33	as big as one , and four is twice as
06:36	big as two anyway , hopefully that was a great
06:39	introduction for our fractions for you . We'll see you
06:42	next time . Bye .

Summarizer

DESCRIPTION:

OVERVIEW:

Fractions Basics - Math Lesson is a free educational video by tecmath.

This page not only allows students and teachers view Fractions Basics - Math Lesson videos but also find engaging Sample Questions, Apps, Pins, Worksheets, Books related to the following topics.