Abacus Lesson 24 // Addition -Complementary Numbers Respect to 10- HUNDRED'S Column Video Lecture | Abacus Master Class:Become an Expert (English) - Personal Learning

lesson 24 learning the abacus
complimentary numbers with respect to
the number 10 in the hundreds column now
this isn't going to be a bit harder than
the last lesson we're just adding
another column of numbers you're used to
this by now so clear your abacus and
let's get going on this because this is
the fun stuff and let's do 364 plus 107
so put the number 364 on your abacus 360
and for 364 plus 107 so we're starting
over here on the left hand side in the
100's column and we are going to put a 1
here piece of cake that one's taken care
of in the tens column there's a 0 do we
do anything here nope there's a 0 in the
tens column we don't add anything to
that and over here in the ones column
there is a 7 so this is where we do the
fun part we can't add we don't have
enough beads to add a number 7 so we
subtract the complement of the number 7
which is the number 3 take that away add
one here in the tens column and what are
we left with is 471 so there it is 364
plus 107 is 471 471 364 plus 107 is 471
all right here we go next one 875 plus
15 piece of cake so 870 75 so I'm kind
of doing this at an angle to make it
work for the camera
hard to get the beads the way you want
them but so there we go
875 plus 15 there is nothing in this one
in the hundreds column there's a zero
there and in the tens column there is a
one with the number fifteen so all we
have to do is just slide up that bead to
add one in the tens column and in the
ones column we need to add a five and
there is not enough beads so that means
we subtract the compliment up here with
that heavenly bead and we add one here
to the tens column did you catch that
so 875 plus fifteen is eight hundred
nine and ninety eight nine and a zero so
875 plus 15 is 898 a nine and a zero all
right let's do a fun one kind of like we
did in last one let's see if you can get
this this is going to be fun we are
going to do 999 plus one now if you're a
pretty sharp kid and I know you are do
you say well no no those no I don't know
you know it plus one is just going to be
the next time rope which is a thousand
well let's see how it works in
applicants world all right you probably
wouldn't talk in that voice but you'd be
yeah anyways okay so 999 plus one
well nothing to do here nothing to do
here over here in the ones column so we
add one to that well there's not enough
beads okay we put on our advocates minds
that means we subtract one alright that
the compliment to the number is nine the
compliment to the number one is nine so
we subtract nine here and add one here
oh goodness look at that there's not we
have to do the same thing here because
there's not we can't add one here
so again we're subtracting the
compliment nine and adding one in the
next column over whoa
same thing again subtract the number
nine and add one in the thousands column
Walsh made of thousands call so 999 is
one zero zero zero which is the number
1000 now the reason that's a piece of
cake problem I know that but one of the
one of the neat things about this is
that's probably the first time in hittin
this that you've done multiple carries
past three columns of digits so we had
999 and we started all the way in the
ones column and when we did the ones
column we had to carry the one over here
but there was already a nine so we had
to do the same thing again and carry the
one to here and then it's the same thing
again until finally we run out of beads
or until we finally have a bead that we
can place a one is zero and a zero so
999 plus one is 1000 let's do a couple
more like that and I think you'll have
it and we can move on to subtraction so
here we go 255 at 2 5 & a 5 there is the
number 255 and we are going to add to
that the number 55 okay we don't have
anything to do in the hundreds column
because 55 has a zero right here and in
the tens column we have a 5 so what do
we do we subtract 5 and add one in the
next column over in the hundreds column
and we've taken care of that we've added
the 50 of 15 5 so now we need to do 5 in
the ones column same thing again
subtract the 5 and add 1 in the next
column to the left so 255 plus 55 is a 3
a 1 and
zero 310 255 255 plus 55 is 310 don't
you love how these met these numbers
just start magically appearing all you
have to do is memorize these compliments
it's almost beautiful in a way I'd like
it it's just I love compliment speed to
do I know I explained this in the
beginning but it might be worth pointing
out again that the word compliment is
not compliment like to give a compliment
compliment means to make hole to bring
in and make complete and I think it's a
good feeling with the abacus when we do
this because we're making numbers
complete and it's good feeling at least
it is for me I might be a little bit
crazy but I think the abacus is pretty
neat because of that it's a good feeling
to make things whole alright let's do
let's do one more here let's kind of
swap things up a bit we're going to do
two we're going to do 27 plus 388 so
let's put the number 27 on our abacus
and we are going to add to that the
number 388 so we're going to start all
the way over here in the hundreds column
and we have to put a three there there
was a zero on the hundreds column before
let's remember even though we put the
number twenty-seven there it's filled
with zeros there's technically something
there even though there it's a zero
there's a zero is considered something
so we're doing zero plus 3 in the
hundreds column and now we need to add
an 8 in the tens column so we're going
to subtract the complement because
there's not enough beads here and we
can't add eight here there's not enough
beads that means we subtract the
complement of eight which is 2 so we
take away two add one in the next column
over and that one is done moving on to
the ones column same thing we're going
to there's not enough beads here so we
subtract
act the compliment which is - and add a
1 here so there it is 27 plus 388 is a 4
a 1 and a 527 plus 388 is 415 all right
let's do one more and I think that will
be a enough
let's do 611 + 199 so 6 1 and a 1 611 +
199 alright so we start over here in the
hundreds column we add a 1 there that's
taken care of
now we need to add a 9 in the tens
column
not enough beads so that means we
subtract the complement which is the
number 1 and then we add another bead in
the next column over all right one more
column to go there's another 9 in the
ones column so we subtract 1 there
because there's not enough beads and the
complement to the number 9 is the number
1 so that's why I took that one way
there and I'm going to add one more to
the tens column and there it is 611 +
199 is a 8 a 1 and a 0 611 + 199 is 810
alright go print off your worksheet and
work through a few more of these
problems to make things whole to make
things complete and get used to working
with that advocacy it really is a lot of
fun to work with the abacus
you