6. Owing to the rising cost of copper, in 1982, the US Mint changed the composition of pennies from 95% Copper + 5% Zinc to 2.5% Copper + 97.5% Zinc to save money in minting pennies. Your favourite aunt has a collection of 5,000 pennies minted prior to 1982 and she intends on gifting the collection to you.
(a) What is the collection's value based on metal content alone? Given: Copper sells for $3.50/pound, Zinc for $1/pound and about 130 pre-1982 pennies add up to 1 lb total mass.
(b) If it costs $0.017/penny in year 2007, is it time for eliminating pennies and round up transactions to the nearest nickel (5 cents)? What effect would this have on the economy? If you decide not to eliminate pennies what can you do to keep minting costs lower?
This solution provides the mathematical rational regarding whether minting pennies is worthwhile in today's economy.