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A cat sleeps for 12 hours each day.
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50 percent of its life is spent asleep.
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Write the missing percentage.
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A koala sleeps for 18 hours each day.
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What percent of its life is spent asleep?
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We know that one day is equal to 24 hours.
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And the question tells us that a cat sleeps for 12 hours each day, or 12 out of 24 hours.
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12 out of 24 is the same as saying half.
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And we know that a half is equal to 50 percent.
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Half a day is 50 percent of a day.
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A koala sleeps for 18 hours each day.
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So we can write this as 18 over 24, or eighteen twenty-fourths.
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To help us calculate what percentage this is, first we need to simplify this fraction.
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We could divide the numerator and the denominator by two to give us nine twelfths.
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Then if we divide the numerator and the denominator by three, we can see the nine twelfths is equal to three-quarters.
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If half is equal to 50 percent, we can use this to work out what a quarter is equal to, which is 25 percent.
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If one-quarter is 25 percent, we can multiply this by three to find three-quarters.
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25 times three is 75.
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So a koala spends 75 percent of its life asleep.
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To find the answer, first we’ve recognised that 12 out of 24 hours is half a day, which is the same as 50 percent.
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Using the information we were given, we worked out that a koala sleeps for 18 out of 24 hours, which is equal to nine twelfths, which is equal to three-quarters.
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We know that one-quarter is the same as 25 percent.
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So three-quarters is equal to 75 percent.
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A koala sleeps for 18 hours each day.
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75 percent of its life is spent asleep.