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https:/.../emt051080p.mp4

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    Welcome to the 50 there in the
    binary number series. In this
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    video I'm going to show you how
    we can deal with fractions in
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    the binary system to be able to
    do that, first we're going to
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    talk a little bit more about the
    power definitions, and then
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    we're going to extend the binary
    place value system. After that,
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    I'm going to show you a couple
    of examples how you can convert
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    binary fractions into decimal
    fractions. So let's extend or
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    recap our knowledge about the
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    powers. So we all remember that
    any number to the zero power, by
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    definition, is always one, and
    if we talk about the negative
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    powers, that is the same as one
    over the positive equivalent
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    over the same power. So what
    does it mean for us? Let's have
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    a look at some examples. So if
    we talk about 3:00 to the minus
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    four, that is just simply one
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    over. Three to four, and if we
    talk about two to the minus
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    three, that is just simply 1 /
    2 to three last example.
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    Done to the minus two, that's
    the same as 1 / 10 to the power
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    of 2. Now Lisa, you need to
    know the negative powers, but
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    remember when we were talking
    about the decimal place value
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    system, we talked about the
    smallest place where you being
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    tend to zero and then then to
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    the one. Dented it too tentative
    310 to the four etc. Now when
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    you look at the powers the
    powers grow by one as we go from
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    right to left. But what happens
    when we go from left to right?
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    The powers decreased by one and
    then if you introduce the
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    decimal point you can further
    extend this place value table so
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    we can talk about 10 to the
    minus one because zero last one
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    is minus one then.
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    Into the minus 210 to the
    minus three etc now.
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    If we look at it with the number
    equivalents, this would be one.
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    This would be 1000.
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    1000 and 10,000. This way this
    would be 1 / 10 this would be
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    1 / 100 because 10 to the power
    of three is 100 and it will be
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    1 / 1000 now.
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    It might be a bit more familiar
    if we look at this way. 1 / 10
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    is 0.11, / 100 is 0.01 and 1 /
    1000 is 0.001, so you might
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    depending on how you would talk
    about it, you either and this
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    format or this format now. Why
    is it good for us? But basically
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    when we start to talk about
    decimal numbers and we can talk
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    about 3.4. Two, but that's
    basically means that I have.
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    Three times. 10 to the
    0 + 4 * 10 to the
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    minus 1 + 2 times.
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    10 To the minus two, so
    the place values are
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    built into the system.
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    Let's look at how it differs
    when we talk about binary
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    numbers. So the binary place
    value system we started with two
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    to the power of 0, two to the
    power of 1 two three power of 2
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    to the power of three, and so
    on. Now we can also introduce
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    something new called a Radix
    point and then we can extend our
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    knowledge of place values to the
    binary system because again, if
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    you look at the powers grow from
    right to left and then buy one
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    and then they decrease by one
    from left to right.
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    So we can extend this to two to
    the minus one.
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    Due to the minus 2, two to the
    minus three, and so on depending
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    on how many digits you want. So
    what are these numbers here?
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    This is 1.
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    This is to this is for this is
    it this one? You are quite
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    familiar with by now. Now the
    radix point comes here. What is
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    2 to the minus one? Well that's
    1 / 2 one is 2 to the minus two
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    that's 1 / 4 what is 2 to the
    minus three? That's 1 / 8
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    remember two to two is 4 and two
    to three is 8. Now again what we
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    learned about the binary place
    value system is that if I'm go
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    from. Right to left. The place.
    Why use double?
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    So you can see you know double
    at 1 S, 2 W, 3 S, 4 W 4 is 8,
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    etc. Now if we go from left to
    right, the place values gets
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    halved, so half of eight is 4.
    Half of four is 2, half of two
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    is 1. Now that's the true on the
    right hand side from the radix
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    point because half of 1 is half
    half of half is 1/4 and half of
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    quarter is an 8. If you can't
    really remember this or you have
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    forgotten about it, try to draw
    them as functions as.
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    Slices of pizza to convince
    yourself that this is how it
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    works, and again, the double
    oven 8 is 1/4 and a double of
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    1/4 is 1/2. Because remember two
    quarters Constanta your half and
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    two 8 sconces down to 1/4.
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    Now again. In
    some cases you will need the
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    fraction numbers, but it's
    always a good thing to know what
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    they look like as decimals. So
    half would always be a .5
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    quarter would be 0.25 and eight
    would be 0.125. Again, if you
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    half in .5 you get .25 and if
    you half in .25 you got.
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    .125 If you're not sure, double
    check it with the Calculator.
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    So why is it good for us?
    Let's look at binary fraction,
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    so let's say I've got 11 radix
    .1 in binary. Now let's see what
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    kind of decimal number is here
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    so. Anything that's on the left
    hand side from the Radix point
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    works like just ordinary binary
    numbers, so the place values
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    here. One and two, and on the
    right hand side from the radix
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    point is the new system that we
    just introduced. So this place
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    value is equivalent to 1/2. So
    what I've got here.
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    Is I bought 1 * 2
    + 1 * 1.
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    Plus 1 * 1/2 This is 2 +
    1, three and a half, which I can
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    also write S 3.5, so that's the
    decimal equivalent of 1, one
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    radix .1 and listen when you're
    reading out the binary
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    equivalent, you don't save, just
    simply point you, say radix
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    point to make the difference
    distinction between binary and
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    decimal fractions. Let's look at
    a different example and see how
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    we can convert that binary
    fraction into its decimal
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    equivalent. So our number this
    case will be one radix, .101.
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    I can again build up the
    binary place value table, so
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    here's the radix point. I will
    have two to zero.
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    2 to the one, two to two, and so
    on. On the left hand side and I
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    would have two to the minus 1,
    two to the minus, 2 two to the
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    minus, three on the right hand
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    side. The equivalent.
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    1. 24 keep the
    point half a quarter.
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    And an 8 now when it comes
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    to our. Binary number.
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    It's very important that you
    place them correctly so the
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    points have to line up so the
    digits I'm using is 1 radix
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    .101. What it means to me? I'm
    using one of the ones.
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    I'm using one of the halves.
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    And I'm using Zita over
    the quarters and I'm
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    using one of the AIDS.
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    Again, 0 times anything. Just
    going to give me zero and what
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    I've got here is 1 + 1/2 plus
    and eight, so how my adding
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    together half aninat? Well,
    whenever I'm adding fractions
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    together I always need to make
    them the common denominator. So
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    what's the common denominator of
    two and eight wow 8 so I know
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    that half is 48 and the 18.
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    Is just 118, so I've got one.
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    Plus four 8 + 1 eight
    altogether makes 5 eight, so
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    one radix .101 in binary is
    equivalent to one and 5 eights
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    in decimal. Now if you want to
    convert the five 8 into
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    decimal.
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    And look just keep it as a
    fraction what you need to do.
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    You need to do the division.
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    So 5 / 8 is the same as 5
    / 8, so let's do the traditional
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    division eight into five dozen
    guy bring into O and appoint an
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    borrow 0. 8 into 50 Go
    6 * 6 * 8 is 48,
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    so we got a two remainder borrow
    0, again 18 to 20 goes twice
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    2 * 8016, Four remainder,
    bringing another zero an 18 to
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    40 goes five times. That means
    that 5 / 8 is equal to
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    0.625, so that means that one
    and 5 eights.
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    Is also the same as 1.625?
    Really depends on if you
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    happy having the equivalent
    instructions or you want
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    them as decimal fractions.
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    Let's look at another
    example. So if I
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    have got 111 radix
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    .1001. The binary place
    values again start with the
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    point. I have one.
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    2 four and I won't need any
    higher place values because I've
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    only got 3 digits and then I
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    have 1/2. 1/4 on
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    8. And the 16. And
    again because I only have got 4
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    digits in here, I only need four
    place values in here. Now let's
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    put the corresponding digits
    under the place values. So 111
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    radix .1001. So what it means to
    us is that we have 1 * 4
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    + 1 * 2 + 1 * 1
    + 1 * 1/2.
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    Plus 0 * 1/4
    + 0 times on
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    8 + 1 *
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    16 Again. Or the place
    values which carry zeros will
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    not be taken into account. So we
    have got 4 + 2 + 1 +
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    1/2 + 16. Now the whole part of
    the number B 4 + 2 + 1
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    seventh and the fraction part of
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    the number. Is half and a
    16 again to add them together? I
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    need to make them into fractions
    with common denominator 16 will
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    be a common denominator, so 1 /
    16 plus half breaking up into
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    sixteens is just 8 / 16. You
    might remember that a half can
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    always be represented with the
    numbers where the ratio top to
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    bottom is one to two. So anytime
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    when. Bottom part of the
    fraction is double of the top
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    part of the fractions. That's
    always 1/2, so one 816 + 1 six
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    teens make 916's, so it's 7 and
    9 / 16. Now I'm going to spare
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    you the long division this case
    and I'm just going to pick up a
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    Calculator and calculate what
    this is equivalent to do. So
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    this will be 7 point.
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    5625 Remember when you want to
    calculate the equivalent of it
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    as a decimal fraction, you just
    need to divide 9 by 16.
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    So 1 one
    1.1001 in binary
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    is equivalent to
    7.5625 in decimal.
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    I hope you now have an idea of
    how to convert binary
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    fractions to decimal fractions
    and had the extended place
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    value system works in the
    following pages you will have
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    some practice questions and
    the answers will follow.
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    So these are the practice
    questions.
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    And here are the answers.
Title:
https:/.../emt051080p.mp4
Video Language:
English
Duration:
15:29

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