You can put this solution on YOUR website!
Ok, here we go!
First change percentages to decimals:
30% = 0.3
80% = 0.8
50% = 0.5
Now you can set up the equation in which x is the number of Kg. of 80% Cu alloy needed.
Simplify and solve for x.
Subtract 0.5x from both sides.
Subtract 6 from both sides.
Now divide both sides by 0.3
13.33... Kg of 80% copper alloy are needed.