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A man weighs 97 and four-fifths of a kilogram on Earth, and his weight on the Moon is one-sixth of its value on Earth.
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Find the man’s weight on the Moon.
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We are given the man’s weight on Earth, and we are told that on the Moon it is one-sixth of this.
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We therefore need to multiply 97 and four-fifths by one-sixth.
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Our first step is to convert the mixed number 97 and four-fifths into an improper or top-heavy fraction.
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We do this firstly by multiplying 97 by five, which gives us 485.
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We then add the numerator to this, giving us 489.
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97 and four-fifths is equal to four hundred and eighty-nine fifths.
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When multiplying two fractions, we need to multiply the numerators and separately the denominators.
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We can cross cancel first, though, as six and 489 are both divisible by three.
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Six divided by three is two, and 489 divided by three is 163 as shown in the bus stop short division method.
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Multiplying the numerators gives us 163, and multiplying the denominators gives us 10.
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We can now convert this improper fraction back into a mixed number by dividing the numerator by the denominator.
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163 divided by 10 is equal to 16 remainder three.
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Therefore, 163 over 10 is the same as 16 and three-tenths.
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The man’s weight on the Moon is 16 and three-tenths of a kilogram.
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This could also be written in decimal form as 16.3 kilograms.