If Sarah has $100 to invest at 8% per year compounded monthly, how long will it be before she has $150?

How many years ill it take for an initial investment of $10,000 to grow to $25,000? Assume a rate of interest of 6% compounded continuously.

John will be buying a used car for $15,000 in 3 years. How much money should he ask his parents for now so that, if he invests it at 5% compounded continuously, he will have enough to buy the car?

Jim wants to buy a computer for $1060. Jim places $1,000 in a bank account that pays 5.6% compounded continuously. After 1 year, will he have enough money?

Which is the better deal? An investment of $2,000 in a bank for one year with 6% interest compounded continuously or an interest rate of 5.9% compounded monthly?

Will invests $2,000 in his IRA in a bond trust that pays 9% interest compounded semiannually. His friend, Kate, invests $2,000 in her IRA in a certificate of deposit that pays 8.5% compounded continuously. Who has more money after 20 years?

The size P of a certain insect population at time t (in days) obeys the model P(t)=500e^0.02t. When will the insect population reach 800?

Strontium-90 is a radioactive material that decays according to the function A(t)=A₀e^-0.0244t where A₀ is the initial amount present and A is the amount present at time t (in years). Assume that a scientist has a sample of 500 grams of strontium-90. How much strontium-90 is left after 10 years?

The half-life of radioactive potassium is 1.3 billion years. If 10 grams is present now, how much will be present in 100 years? Use the formula A(t)=A₀e^kt

A fossilized leaf contains 70% of its normal amount of carbon-14. Assume the half-life of carbon-14 is 5600 years. How old is the fossil? Use the formula A(t)=A₀e^kt

A piece of charcoal is found to contain 30% of the carbon-14 that it originally had. When did the tree from which the charcoal came die? Use 5730 years as the half-life of carbon-14. Use the formula A(t)=A₀e^kt