**Practice Problem 5**

What is the value of a gold ingot 20.0 cm long by 8.5 cm wide by 6.0 cm tall, if the mass of a cubic centimeter of gold is 19.3 grams and the price of gold is $356 per ounce?

**Solution**

Because the problem gives the length, height and width of the gold ingot, we might start by calculating the volume of the ingot.

V = (20.0 cm x 8.5 cm x 6.0 cm) = 1020 cm^{3}

This calculation is useful because we know something about the mass of a cubic centimeter of gold.

1 cm^{3} = 19.3 g

We can therefore calculate the mass of the ingot in grams.

We can now convert from grams into pounds.

We can then calculate the number of ounces of gold in the ingot.

We are now ready to use the price of gold to calculate the value of the ingot in dollars.