For problems 1 through 3, write an exponential equation to represent each situation. Be sure to define your variable. 1. A person deposits $1,500 into a savings account that generates 7.3% interest per year. When will the account contain $8,000?

2. The population of a town increases 3% every year. There are currently 25,000 people living in the town. When will the town have 40,000 people?

3. The price of gas is declining 2% each week. The price is currently $2.06 per gallon. When will the price be $1.90 per gallon?

For problems 4 and 5, write an exponential equation to represent each situation, and solve the equation to answer the question. Be sure to define your variable and show all of your work.

4. An amount of bacteria is quadrupling every eight minutes. If there are currently five bacteria, when will there be 5,120 bacteria?

5. The half-life of a substance is 120 years. If there are currently 300 grams of the substance, when will 75 grams remain?

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