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If a team won nought point five six four of the games it played, determine the percent of the games they lost or drew.
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Well in this question, nought point five six four is the proportion, out of one, of the games that the team won.
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Now if you don’t win a game, you either lose it or draw it.
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So the lost or draw must be the rest of the games.
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And given that one represents the proportion of all of the games that they’ve played, the proportion they lost or drew must be one minus nought point five six four.
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Let’s look at two different ways of calculating one take away nought point five six four.
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First, let’s think about one point zero zero zero minus nought point five six four.
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Okay, let’s look at the first column on the right there, zero take away four.
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Well I can’t do that, so I’m gonna need to borrow one from the next column.
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Ah, but that’s a zero so I can’t borrow one from there, so I borrow one form the next column.
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And I can’t borrow one from there cause that’s a zero, so I’ll have to borrow one from the next column.
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So that makes that a zero, and I’ve borrowed one from here.
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Now I’ve got ten in the tenths column.
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So what I can do is borrow one from there, which leaves me with nine in the tenths column and ten in the hundredths column.
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Now I can borrow one from there, from those ten hundredths for my thousandths column.
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Right, now we’re in business.
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Ten minus four is six.
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Nine minus six is three, and nine minus five is four.
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And then I’m gonna put my decimal point, and zero minus zero is nothing.
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So the answer is: Zero point four three six.
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Now let’s take an alternate approach.
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Let’s consider these two numbers on the number line.
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What’s the difference between nought point five six four and one?
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Well if I add nought point nought nought six, then I’m gonna get four plus six in this column, which is gonna round me up to nought point five seven.
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And if I now add nought point nought three, then I’m going to add one to this seven hundredths to make it nought point six.
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And then lastly, to get from nought point six all the way up to one, I need to add nought point four.
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So to go from nought point five six four up to one, I needed three steps.
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Nought point nought nought six, which took me up to nought point five seven.
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Another nought point nought three, which took me up to nought point six.
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And then another nought point four, which took me up to one.
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So if I add those three steps together, nought point four plus nought point nought three plus nought point nought s- nought six is nought point four three six.
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So I get the same answer, but I’ve looked at it in an entirely different way.
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So if all of this carrying business over here confuses you and you can visualise these steps towards one a bit more easily, then use that method.
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But if you’re happy with the carrying method, then maybe not having to do the drawings might be easier.
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That first method might be quicker for you.
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Either way, the proportion of games that they lost or drew is nought point four three six.
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But we need to determine this as a percent of the games they lost, not just as a proportion out of one.
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Now percent means out of a hundred, so nought point four three six is out of one and we want to get the answer out of a hundred.
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We need to multiply this by a hundred in order to get our answer.
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Now nought point four three six times a hundred is forty-three point six.
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So our answer is: Forty-three point six percent of games were lost or drawn.