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

Question

anonymous · Answer

I would like to ask for help on how to set this problem up please

anonymous · Answer

Sylvanite:  (100 g sylvanite/ 28 g gold) * 81g gold = 289.29 g sylvanite

anonymous · Answer

You want to set it up so you can cancel units out and have "g sylvanite" left over.

anonymous · Answer

Let x = amount of sylvanite you dig up.
0.28x = amount of gold you get because 28% of salvanite is gold

If you want 81g of gold, then...
0.28x = 81
Divide by 0.28
x approx = 289.286

anonymous · Answer

You all are great thank you

anonymous · Answer

Does the unit-canceling thing make sense?

anonymous · Answer

yes, I had the number in the wrong place and my answer wasn't making any sense to me

anonymous · Answer

http://student.ccbcmd.edu/~cyau1/121PractProbOnUnitConversionSp2005.pdf

anonymous · Answer

Thanks again I did another similar problem and it made sense