Algebra 2 help?

Question

1. The Mendes family bought a new house 7 years ago for $119,000. The house is now worth $189,000. Assuming a steady rate of growth, what was the yearly rate of appreciation? Round your answer to the nearest tenth of a percent (1.2% etc)

 

2. The annual Gross Domestic Product (GDP) of a country is the value of all of the goods and services produced in the country during a year. During the period 1985-1999, the Gross Domestic Product of the United States grew about 3.2% per year, measured in 1996 dollars. In 1985, the GDP was $577 billion. I what year did/or will the GDP equal $2.2 trillion?

3. An anthropologist finds bone that her instruments measure it as 0.717% of the amount of Carbon-14 the bones would have contained when the person was alive. How long ago did the person die?
The half life of carbon 14 is 5,730 years. Round your answer to the nearest thousand.

Answer 1

189 = 119e^7r find r = annual rate of growth

take natural logs of both sides

ln(189/119) = 7r

divide by 7

r = (1/7)ln(189/119) = about .066 = 6.6% appreciation annually