Since Sylvanite only contains 28% gold by mass, then to obtain 81.0 grams of gold, x amounts of sylvanite must be mined. To determine x, we divide 81 grams by 28%. This equation is shown below:
0.28X = 81
X = 81/0.28
X = 289.29 grams
Therefore, 289.29 grams of sylvanite must be dug up to obtain 81 grams of gold.
X-30+x-30+x=180
3x-60=180
3x=240
X=80
Answer:
8+2j like you say let j be the variable and more than means+