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https:/.../emt061080p.mp4

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    Hello and welcome to the 6th
    video in the binary series. So
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    you more or less now understand
    how you can convert a binary
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    fraction into a decimal
    fractions. But how can we do it
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    the other way around? So let's
    say I have got a fraction, say 4
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    3/4. How can I convert that
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    into? A binary fraction. Again,
    let's call up on the place value
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    table. So the rate explained
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    is here. 1248 and
    on this side,
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    half or quarter.
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    And an 8 now what happens in
    here when it comes to the whole
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    part, the four. I know that I
    can build up from using one for
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    an nothing else, so I will need
    the place value holders.
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    And then the radix point now 3/4
    by the obvious thinking would be
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    always just to put the three in
    here. Don't forget that we are
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    in the binary, so we can only
    use ones and zeros, so we can't
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    use a 3, but there are quarters.
    So what happens if I take out
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    one of those quarters? So if
    I've got 3/4 and I take away 1/4
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    from it, I am going to left with
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    two quarters. But hold on, two
    quarters is exactly the same as
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    a half. Well, that solves my
    problem, because then I can just
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    put a digit here. So you might
    have spotted this by knowing the
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    half and a quarter makes up 3/4.
    But this means that four and
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    three quarters in decimal is the
    same as 100 radix .11.
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    In binary. Let's look
    at another example.
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    3 and 5
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    eights. Place values again.
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    1. 24 Radix
    point half a
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    quarter. And an 8.
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    Now three is 2 + 1, so I'm going
    to use G of this place values
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    Radix point here, but when it
    comes to 58 again, I'm going to
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    be in a little bit of a trouble
    to find out what combinations
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    going on in here, and therefore
    you need to have quite a good
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    understanding of manipulating
    fractions, adding and
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    subtracting them. So if you're
    not sure, please do recap days,
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    so don't forget that there are
    loads of very good online
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    resource is that you can recap
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    on. Had to add and subtract
    fractions, so let's see what
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    happens with the five 8 now.
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    I can use up one of the AIDS,
    but I can use up only one of
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    them. So what happens if I take
    an 8 away from the 458? So I've
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    got 48 left now that Tendai,
    because remember any function
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    that has got twice as much as
    the bottom is at the top, always
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    cancers down to half, so the
    remainder here is just half.
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    That means I need a place for
    the zero here, so three and five
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    eights in decimal is the same
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    as. 11 radix .101.
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    In binary.
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    Let's look at a slightly
    different decimal equivalent, so
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    6.25 in decimal. What does it
    look like in binary? Now for
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    this particular format, it's
    good to know the fraction and
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    decimal fraction equivalent, so
    again, the whole part of the
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    table will be 1248, etc. Radix
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    point. And then we would have
    half a quarter and an 8 here.
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    Now.
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    This part of the table is the
    same, but beyond the radix point
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    because I have got the decimal
    fractions. Now I would need to
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    look at the decimal fractions
    here, so half is 0.5, a quarter
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    is 0.25. Well, that tells you
    something that and then eight is
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    0.125. So Luckily this is a
    rather simple function to
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    convert into binary fraction
    because six will be the sum of.
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    Four and two. So I need
    a placeholder zero for
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    the one radix point 1/2.
    I'm not using because all
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    I'm using is .25 so 6.25
    in decimal is the same as
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    110 radix .01 in binary.
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    Let's look at a
    somewhat more complicated
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    example, so 5.3125.
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    In decimal, what is it equal to
    in binary? So again, right down
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    the place values. So on the left
    hand side of the radix point
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    everything is the same as it
    always has been.
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    And on the right hand
    side now I have got
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    0.5 zero, .25, zero, .125
    and then I have got
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    0.0625.
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    So let's see which one of these
    I need to use to make up my
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    #5 is 4 and one and on the
    other side of the radix point.
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    Now 0.5 is too big because the
    0.3125 is less than 0.5, so I'm
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    not going to use this. What
    happens if I take 0.25 out from
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    my decimal fraction part? So if
    I've got the 0.3125?
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    And I need to take away the 0.25
    from it. What do I left with? So
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    first of all to carry out this
    obstruction I need to fill in
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    the zeros 5 -- 0 is five 2 -- 0
    is two 1 -- 5. I cannot do so I
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    need to borrow.
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    11 -- 5 is Six 2 -- 2 is 0.
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    .0 -- 0 is zero. Well that
    seems rather lucky because the
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    0.3125 is just simply the sum of
    0.25 and 0.0 sixty five. So
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    that's another place value. Hold
    up there for.
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    5.3125 in decimal is
    equivalent to 101 radix
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    point. 0101
    in binary.
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    Now, I hope that seeing these
    examples will give you a good
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    idea about how to go around
    converting binary fractions to
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    decimal fractions or decimal
    fractions into binary fractions.
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    Also, you probably have a little
    bit of an idea about how
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    difficult or hard inconvenient
    converting decimal fractions
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    into binary functions can be not
    to further add to this
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    difficulties, what if I would
    need it to convert, such as
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    simple fraction? S3 and 4 /. 5
    now there are no fifths in the
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    binary place value table because
    these place values are just
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    halves of Hobbs, etc etc. So
    there are no 15 that so you can
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    sit around there quite a bit of
    time to sort of think about what
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    I can do. How can I be that
    forfeits out of.
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    Hop hop squatters, 8 entrance,
    etc. Another rather simple
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    example that could be also
    problematic. Let's say if I
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    wanted to convert 5.4 again, .4.
    What combinations of 0.5, zero,
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    .25, zero point 25, etc would
    make up the .4 bit. This sort
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    of draws your attention to the
    limitations of the binary
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    fractions. While not every
    single decimal fractions.
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    Can be expressed as a finite
    binary fraction. We can always
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    extend the system to use more an
    more digits to express the
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    fractions, but unfortunately
    this is an inherent property of
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    the binary system.
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    In the next video I will show
    you how we can try to come
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    about these problems and see a
    different method of converting
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    decimal fractions into binary,
    which can make things slightly
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    easier. But for now I'm going
    to leave you with some
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    practice questions and you
    will find the answers to these
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    after the questions.
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    So these are the practice
    questions.
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    And here are the answers.
Title:
https:/.../emt061080p.mp4
Video Language:
English
Duration:
10:13

English subtitles

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