context: 9 carats - the mass of the noble metal is 0.375 of the weight of the alloy; 12 carats - the mass of the noble metal is 0.500 of the weight of the alloy; 14 carats - the mass of the noble metal is 0.583 of the weight of the alloy; 18 carats - the mass of the noble metal is 0.750 of the weight of the alloy; 21 carats - the mass of the noble metal is 0.875 of the weight of the alloy; 22 carats - the mass of the noble metal is 0.916 of the weight of the alloy; 23 carats - the mass of the noble metal is 0.958 of the weight of the alloy; 24 carats - the mass of the noble metal is more than 0.999 of the weight of the alloy, that is, the metal in its pure form.
question: How many carats of gold are there in 999?
answers.text: 24