chem 111
posted by Heather .
Average density of a coppercoated iron BB is 8.00g/mL. If the density for copper is 8.92 g/mL, and the density for iron is 7.43g/mL, what is the percentages of copper and iron in a BB?

Bob Pursley answered this for you earlier. If you have a specific problem, show your work to where you get stuck, explain what you don't understand for the next step and perhaps someone can help you through it.

well i did the problem to my understanding and I ended up getting this: fraction for for Fe: .004 and for Cu: .006?? and he said it should equal 1?? where did I go wrong it equals .01??

I was wondering if you could tell me if the answer is Fe: 40% and Cu: 60%???

In my explaination, I used fraction or decimal percents, not percents. a fraction percent of .4 is 40 percent.