Question 1194021
the calculator i used for this is the ti-ba-ii busness analyst by texas instruments.


for the first part, the inputs were:
present value = 0
payment at the end of each year = 1000
number of years = 3
interest rate per year = 8%
output was future value = 3246.4


for the second part, the inputs were:
present value = -3246.4
payment at the end of each year = -1000
number of years = 4
interest rate per year 10.25%
output was future value = 9454.513243


for the third part, the inputs were:
present value = -9454.513243
payment at the end of each year = -1000
number of years = 3
interest rate per year = 9%
output was future value = 15521.96883


the total investment was 1000 * 3 + 1000 * 4 + 1000 * 3 = 10,000
the total interest earned was 15,521.96883 minus 10,000 = 5,521.96883.


for the last part, the inputs were:
present value = 0
payment at the end of each year = -1000
number of years = 10
future value = 15521.96883
output was interest rate = 9.448451033%


here's what it looks like in a year by year display using excel.


<img src = "http://theo.x10hosting.com/2022/050522.jpg" >


here's what the inputs and outputs look like using arachnoid financial calculator at <a href = "https://arachnoid.com/finance/index.html" target = "_blank">https://arachnoid.com/finance/index.html</a>


<img src = "http://theo.x10hosting.com/2022/050523.jpg" >


<img src = "http://theo.x10hosting.com/2022/050524.jpg" >


<img src = "http://theo.x10hosting.com/2022/050525.jpg" >


any differences in results are due to intermediate rounding by the online calculator.


let me know if you have any questions.
theo