Population Growth and Decay: Solve algebraically using logarithms. Complete all work on a separate sheet of paper.
1) The population of a city is 475,000 and found to be increasing at a rate of 3.75% per year. When will the population reach 1,000,000? Round your answer to the nearest thousandth.
2) The population of a city is 123,000 and is found to be decreasing at a rate of 2.375% per year. When will the population reach 50,000? Round your answer to the nearest thousandth.
3) In 1890 the population of a town was 6,250 and is found to be increasing at a rate of 3.57% per year. Approximately what will the population be in 1915? 1940? Round your answers to the nearest 100 people.
4) The half-life of a certain radioactive substance is 14 days. There are 6.58 grams present initially. When will there be 1 gram remaining? Round your answer to the nearest thousandth.
5) The half-life of a certain radioactive substance is 65 days. There are 3.5 grams initially present. When will there be 1 gram remaining? Round your answer to the nearest thousandth.
6) How long will it take$1,000 to grow to $2,500 at 8% compounded monthly? Round your answer to the nearest thousandth.
7) How long will it take $4,600 to grow to $6,000 at 5% compounded quarterly? Round your answer to the nearest thousandth.
8) If $3,500 is invested at 7% compounded annually, how long will it take to accumulate $10,000? Round your answer to the nearest thousandth.
9) How long will it take $1,250 to double at 7% compounded monthly? How long will it take it to triple? Round your answers to the nearest thousandth,
