Sylvanite is a mineral that contains 28.0% gold by mass. Determine how much sylvanite would you need to dig up to obtain 81.0 g of gold.

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.