MATH HELP
posted by Sammy .
Derrick is investing $1,000 at 5% interest and Anna is investing $750 at 7% interest. Both interest rates are compounded annually. When will they have the same amount saved? (Hint: 1.05t/1.07t =(1.05/1.07)t )

we want
1000*1.05^t = 750*1.07^t
(1.05/1.07)^t = 3/4
.9813^t = .75
t = log(.75)/log(.9813) = 15.24 years
Extra credit: after that point, who gets the larger amount? 
calculate the compound interest on an investment of $18,000 at 8%, interest compounded quarterly, for 15 months.
Respond to this Question
Similar Questions

Compound Interest
A bank offers a rate of 5.3% compounded semiannually on its four year GICs(Guaranteed Investment Certificates). What monthly and annually compounded rates should it quote in order to have the same effective interest rate at all three … 
compounded interest
A bank offers a rate of 5.3% compounded semiannually on its four year GICs(Guaranteed Investment Certificates). What monthly and annually compounded rates should it quote in order to have the same effective interest rate at all three … 
math
an investor is considering investing £5000 over five years in a scheme which offers compound interest of 3.4% compounded annually. what is the total interest paid. 
Math 20(interest rates)
Determine the amount of interest charged on a loan of $5000 at 6.75% per annum, compounded semiannually for 3 years. 
finance
If we invest money for 10 years at 8% interest, compounded semiannually, we are really investing money for ______ six month periods, during which we receive _______ percent interest each year. 
Compound interest
Hello My teacher skipped over this and I have no clue how to do this or the equations. Help would be wonderful thank you If 6000 dollars is invested in a bank account at an interest rate of 10 per cent per year, find the amount in … 
engineering economic
Ahmad is considering investing RM2000 to Ali's project at an interest rate 6% compound annually for 5 years or investing RM2000 to Rosli at 7% per year simple interest for 5 years. From your point of view which option is better and … 
investing
. Jamie Thompson is thinking about investing in some residential incomeproducing property that she can purchase for $200,000. Jamie can either pay cash for the full amount of the property or put up $50,000 of her own money and borrow … 
math
Simple interest the simple interest received from investment is directly proportional to the amount of the investment. By investing $4000 in a municipal bond you obtain interest of $280 at the end of 1year. Find a mathematical model … 
investing
Lily invests $4,000, at 6% interest, compounded quarterly for 5 years. Calculate the compound interest for her investment by using Table 111.