Precious metals and gems are measured in troy weights in the English system:
24 grains = 1 pennyweight (exact)
20 pennyweight = 1 troy ounce (exact)
12 troy ounces = 1 troy pound (exact)
1 grain = 0.0648 gram
1 carat = 0.200 gram
a. The most common English unit of mass is the pound avoirdupois. What is one troy pound in kilograms and in pounds?