A country has 157 years of oil reserves at the current rate of consumption. Suppose that the demand for oil in the country is 8,000,000 barrels per year. Furthermore the oil is consumed at a rate that increases 3.1% per year.

(a) How long will the oil reserves last?
Answer:

(b) Suppose a recent discovery has doubled the quantity of oil reserves. Now how long will the oil reserves last?
Answer: