Ocean water contains .9 ounces of gold per ton. Method A costs $550 per ton of water processed and will recover 90% of the metal. Method B costs $400 per ton of water processed and will recover 60% of the metal. The two methods require the same capital investment and are capable of producing the same amount of gold each day. If the extracted gold can be sold for $1,750 per ounce, which method should be recommended? The supply of ocean water is essentially unlimited.
Hint: Work this problem on the basis of profit per ounce of gold extracted.