Question 1095577
Pure gold is 100% gold.
14 karat gold is  {{{14/24=7/12}}} of gold.
16 karat gold is  {{{16/24=4/6=2/3}}} gold.


{{{system((x(7/12)+y*1)/20=2/3,x+y=20)}}}


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{{{y=20-x}}}
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{{{x(7/12)+y=20(2/3)}}}

{{{7x+12y=20*2*4}}}

{{{7x+12(20-x)=8*20}}}

{{{7x+12*20-12x=8*20}}}

{{{-5x=8*20-12*20}}}

{{{5x=4*20}}}

{{{x=16}}}


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16 grams of the 14 karat gold
and
4 grams of the pure gold
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