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so let's talk about bar models
a bar model is something you can use to solve a math problem. it helps you
organize the information you have visually so you can see what you have
and what's missing and
maybe some things you can try. you know in math we use models of of all
kinds
when you think of the word model you might be thinking of like someone who's
just ridiculously good looking for a living you know like your teacher
but you know a model is also just a small version of something
you know like a model airplane
or a model of the solar system
a model is just something we make that represents something else and in math we do
that all the time
so the essence of the bar model method is using spatial equality
which you can see not coincidentally in an equal sign
the top bar is the same as the bottom bar they take up the same amount of space
they have spatially equality
in a bar model we're gonna use you know the things that we know the parts of
things to compare or calculate the total or the missing amount in the
other bar
you know having that right in front of you what you see exactly what
you have or don't have
and it makes it pretty intuitive to figure out
what you're supposed to do
uh... if only everyone did that you know use use what you know to solve problems
don't just make stuff up like that
one weird kid on the playground
you know math maybe more than any other subject requires us to be abstract
thinkers at a very early age whether we're ready for it or not
and you know some ways of dealing with that are to use lots of
hands on manipulatives and if you don't have that ... hey, grab a bar model
so in this example if we know that top bar represents a total of ten
than the bottom bar which is spatially equal began spatial the space it takes
up uh...
than the bottom or is also equal to ten units and we can divide the bar into
equal parts and label them
from one to ten
uh... you can also represent that equality with other things like tally
marks
uh... you can put ten dots in there
uh... where you can do it more of straggling with the numbers whatever
best suit your skill level
if you have the total value of a bar which in this case is ten
and you have a partner apiece in this case it's three
they worry is the qualities of the bars they should both be equal they should
both be ten uh... we're going to use that to find a difference of the missing
part in you can use whatever strategies are best that you can count up you can
subtract
and missing part here seven seven three together make
and the bar model what's great about it is it adapts with your skill level as
your number since grows you know how to break apart
and put together numbers
without drawing things you'll begin to instantly you recognize the missing
parts
you have a total of ten and you have five in you know that other pieces gotta
be five
if you have six it's twenty four
word yet seventy any three
or the state
you need to
and if it's a nine
yeah anyone
the bar model strategy is also called park park
and in most problems will be looking for the whole
or total or the
largest her final amount
and assigning that label in value if you have it
to the top bar
and them below you put the parts that are going to make up that whole or total
margin final now
if you have all the parts
uh... wiki of twelve and six
menu we're gonna put them together
to find the whole
twelve plus six
we needed a total which is
uh... eighteen
there may be other problems where you know what the total the final amount is
looked so you have a hundred and twenty and you know one of the parts is eighty
where we can reuse what we have we're gonna take away eighty from the total
one hundred twenty to find the missing part the differences
forty
and that eighteen forty together in equal a hundred and twenty which is the
whole
and in some of the problems you'll be dealing with equal groups uh... but it's
just as easy here i get six groups of eight
uh... i don't have the total sum reporting all those groups together six
times a gives me a total of forty eight
uh... tonight will be dividing also will get into that later
that's basically it pay the best way to learn the bar model strategies just
practice mess-up
figure out what to do next time build some background knowledge gets an
experience before you know what you'll be a bar model master everyone will work
acting and you know that
uh... which another some property with that said kinda personally show hope to
be
work mcentee complicated like a lot of problems in life like my problems in
life
companies
uh... one specific methods can work for everything but if you stick with the
general problem-solving approach of understand plants all over the track
barnett is a great way to start uh...
you know after thinking about the who in the white in a problem in visualize
what's happening in my head
on as myself to why have the total to one of the final map that would be much
harder
and i go to ok do i have joined the equal real specific help me know what to
draw
uh... what operation i might have to work on
i'm in a minute organize the information
uh... in label everything that helps you know what numbers go where
when you label everything and see how the different quantities you have fit
together
it so much easier to spot mistakes enough you're doing the right thing
so let's put it all together in a typical one-step problem you're gonna
ask yourself do you have the total the final the biggest the everything
if you don't and you have the parts then you're gonna be combining those parts to
get the total
and then there's different ways to combine the numbers honestly it ask
yourself well do i have equal groups were
arise equal parts
if you don't
then we're just gonna add those pieces together you might have to you might
have to read might have however many you have
uh... but then it becomes an addition problems putting those numbers together
and then if you do have equal groups hate even better we're gonna do repeat
addition also known as multiplying
back at the top let's say you do have the total
uh... and you're missing a piece you have one part that there's someone known
there
uh... that you don't now i guess if it's a nun unknown you don't know i think
you're going to separate your to separate the peace you have from the
total
sewing excuse of well they want me real still have equal parts
if no then you're just gonna subtract you take the piece that you have away
from the total and that'll give you the piece that's left over also known as the
difference which is a subtraction problem
if you do you have equal groups for equal parts haiti
we're gonna divide that's repeat subtraction
and you'll see that a lot uh... in problems they have fractions your
dividing your total up into equal groups and you have so many of those pieces
that's
uh... that's just working on fractions it makes it really easy you can even all
my gosh use those keywords or code words that your teacher major memorize to
uh... make sure you're doing the right operation
so let's put this in a practice with a real problem if you're still with me we
get tina has three cats
mastro goldfish jury has two dogs how many pets do they have all together
well think about the to susan this problem while there's three people tina
mageary marty thinking about uh... what's going on here
how about the what what's my number fax one of my looking for well
pacts three cats twelve goldfish in two dogs
i'm gonna start to drop my bars and thing about war what's the big number
what's the total what's everything do i have uh... asylum
uh... well you know they're asking me for that date they want to know what we
have altogether instead my data facts are the parts that pieces
are the all parts
no
i've got a group of pets there's three cats twelve
goldfish two dogs is different amounts to those thing so
again just combine those together in the most simple way which is addition
so i'm gonna leave all my bars it's very important to get peps up top that's the
total that i can goldfish cats and dogs i fill in the numbers that i have for
everything
and then i'm gonna combined those just by adding a month
and it's seventeen and then i liked her
your teacher like you to do this radical pleats sentence for the answer he now
and so there it is a very brief and yet somehow still long
handlers teachers always do that introduction of the world of or models