college
posted by inny on .
A bag contains a mixture of copper and lead BBs. the Average density of the BBs is 9.50g/cm^3. Assuming that the copper and lead are pure determine the relative amounts of each kind of BB

Look up the densities of lead and copper. Lead: 11.34 g/cm^3. Copper: 8.93 g/cm^3
If f is the fraction of the BBs that are copper (which would be a volume fraction), then 1f is the fraction that are lead, then
8.93 f + 11.34(1f) = 9.50
Solve for f