A 9 carat gold ornamental casting is made from an alloy of metals. The table below shows the mass of different metals in the casting.
Table 1
| Metal | Mass of metal (g) |
|---|---|
| Gold | 60.0 |
| Copper | 80.0 |
| Zinc | 20.0 |
The total mass of the casting is 160.0 g.
Castings can also be made from 21 carat gold. The ratio of the mass of gold in 21 carat gold compared to 9 carat gold is 21:921 : 921:9.
Calculate the mass of gold in a 21 carat gold casting of mass 160.0 g.