Serway & Jewett — Fluid Mechanics: Problem 39

In 1983, the United States began coining the one-cent piece out of copper-clad zinc rather than pure copper. The mass of the old copper penny is 3.083 g and that of the new cent is 2.517 g. The density of copper is \(8.920 \text{ g/cm}^3\) and that of zinc is \(7.133 \text{ g/cm}^3\). The new and old coins have the same volume. Calculate the percent of zinc (by volume) in the new cent.