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Write 48 centimetres as a fraction of four metres.
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Give your answer in its simplest form.
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Before we start this question, we need to remember the conversion that 100 centimetres is equal to one metre.
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Multiplying both sides of this conversion by four tells us that four metres is equal to 400 centimetres.
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We now have both of our values written in the same units.
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We were asked to write 48 centimetres as a fraction of four metres.
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This means that we need to write 48 over 400.
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We’ve now completed the first part of the question.
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However, we were also asked to give the answer in its simplest form.
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This involves cancelling or breaking down the fraction.
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To ensure that we have an equivalent fraction, we need to remember that whatever we do the top we must do to the bottom.
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When we are dividing the numerator, we must divide the denominator by the same number.
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There are lots of ways of cancelling this fraction.
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You might have noticed that both 48 and 400 are divisible by four.
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48 divided by four is equal to 12, as 12 multiplied by four equals 48.
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Dividing 400 by four gives us 100.
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This fraction can be simplified or cancelled again.
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Both two and four divide into the numerator and denominator.
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This means that we could divide the top and bottom either by two or by four.
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Dividing 12 by four gives us three, and dividing 100 by four gives us 25.
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Remember, dividing by four is the same as finding a quarter of a number.
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And we know that one-quarter of 100 is 25.
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The numbers three and 25 have no common factor apart from one.
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Therefore, the fraction is now in its simplest form.
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48 centimetres as a fraction of four metres in its simplest form is three twenty-fifths or three over 25.