#common_fraction__simple_fraction  the quotient of two integers
  supertype:  fraction  the quotient of two rational numbers
  subtype:  half__one-half__onehalf  one of two equal parts of a divisible whole; "half a loaf" or "half an hour" or "a century and one half"
     subtype:  fifty_percent__fiftypercent  a half expressed as a percentage
     subtype:  mediety__moiety  one of two (approximately) equal parts
  subtype:  one-third__onethird__third__tierce  one of three equal parts of a divisible whole; "it contains approximately a third of the minimum daily requirement"
  subtype:  two-thirds  two of three equal parts of a divisible whole
  subtype:  one-fourth__onefourth__fourth__quarter__fourth_part__twenty-five_percent__quartern  one of four equal parts; "a quarter of a pound"
  subtype:  three-fourths__threefourth  three of four equal parts; "three-fourths of a pound"
  subtype:  one-fifth__onefifth__fifth__fifth_part__fifthpart__twenty_percent  a fifth part
  subtype:  one-sixth__onesixth__sixth  a sixth part
  subtype:  one-seventh__oneseventh__seventh  a seventh part
  subtype:  one-eighth__oneeighth__eighth  an eighth part
  subtype:  one-ninth__oneninth__ninth  a ninth part
  subtype:  one-tenth__onetenth__tenth__tenthpart__ten_percent__tenpercent  a tenth part; one part in ten
  subtype:  one-hundredth__onehundredth__hundredth__onepercent  one part in a hundred
  subtype:  one-thousandth__onethousandth__thousandth  one part in a thousand
  subtype:  one-millionth__onemillionth__millionth  one part in a million
  subtype:  one-billionth__onebillionth__billionth  one part in a billion
  subtype:  one-trillionth__onetrillionth__trillionth  one part in a trillion
  subtype:  one-quadrillionth__onequadrillionth__quadrillionth  one part in a quadrillion
  subtype:  one-quintillionth__quintillionth  one part in a quintillion

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