SOLUTION: Question 1. How long will it take for an investment to double at 7%p.a. compounded monthly? Question 2. How long will it take for regular monthly deposit of $200 to accrue to

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Question 1038087: Question 1.
How long will it take for an investment to double at 7%p.a. compounded monthly?
Question 2.
How long will it take for regular monthly deposit of $200 to accrue to $15000 if interest is paid at the rate of 7.25%p.a. a compounded quarterly?
Question 3.
What is the present value of an annuity where $160 is deposited at the end of each quarter for 3.5 years into an account bearing 14% p.a. interested compounded monthly?
Question 4.
At the end of each quarter $700 is invested in an account. The account pays interest at 8% p.a compounded monthly. How much is in the account after two years?

Answer by Boreal(15235)   (Show Source): You can put this solution on YOUR website!
Can do the first two here.
A=Ao(1+.07/12)^12t
A=2 Ao
2=(1+.0058333)^12t
ln of both sides
ln2=12t*ln (1.00583333)
without rounding, divide both sides by ln(1.0583333)
then divide both by 12
t=9.93 years
The rule of 72 would say about 10 years. This is reasonable.
--------------------------
15000=200(1+(.0725)/4)^4t
75=[1+(.0725)/4)]^4t
ln 75=4t ln (1+(0.0725)/4))
t=60.09 years

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