Download Suppose that you plan to need $10,000 in thirty

Logarithmic Applications
1.
Suppose that you plan to need $10,000 in thirty-six months' time when your child starts attending
college. You want to invest in an account yielding 3.5% interest, compounded monthly. How much should
you invest?
2. Certain bacteria, given favorable growth conditions, grow continuously at a rate of 4.6% a day. Find the
bacterial population after thirty-six hours, if the initial population was 250 bacteria.
3. A special fund compounds interest monthly. If a principle of $14,000 yields $45,510 after a 5-year
term, find the annual interest rate.
4. Mrs. Baldwin invests $1000 in a savings account at 6% annual interest compounded monthly, how long
will it take to double?
5. Jessica invests $15,000 at an annual percentage rate of 8%. How much money will she have after 6
years if the interested is compounded continuously?
6. How much money should you save in an account paying 5% interest compounded quarterly if you want to
have $6000 in 6 months?
7. Lu Electronics offers you your very first credit card that charges 12.49 % interest to its customers
and compounds that interest monthly. Within one day of getting your first credit card, you max out the
credit limit by spending $1,200.00. If you do not buy anything else on the card and you do not make any
payments (it’s that special introductory offer), how much money would you owe the company after 6
months?
8. Suppose Ms. Lincoln only has $3500 to invest but still wants $4000 for a hot tub. He finds a bank
offering 5.25% interest compounded quarterly. How long will she have to leave her money in the account
to have $4000?
9. ABC Bank is offering to double your money!  They say that if you invest with them at 6% interest
compounded quarterly they will double your money. If you invest $1500 in the account, how long will it
take to double your money?
10. How long will it take $4000 to triple if it is invested at 5% compounded continuously?
11. Ryan plans to put her graduation money into an account and leave it there for 4 years while she goes to
college. She receives $750 in graduation money that she puts it into an account that earns 4.25%
interest compounded semi-annually. How much will be in Ryan’s account at the end of four years?