Solved: Calculator Issues? Annuity Value at 6 Years w/ 6.8% Compounded Annually

I would not want to do the easier arithmetic intermediate step by hand for that particular example.In summary, to save money, you put $3000 at the end of each year in an annuity that pays 6.8% compounded annually. Using the formula A=P[(1+(r/n)nt)-1]/(r/n), you would have saved $44,103 at the end of six years. However, there was a mistake in the parentheses used in the calculation and the correct answer is $21,352. When inputting the values into a calculator, it is important to pay attention to the placement of parentheses to ensure accurate calculations.
  • #1
yumito
17
1

Homework Statement


To save money you put $3000 at the end of each year in an annuity that pays 6.8% compounded annually. Use the formula for the value of an annuity.
The Given Formula:
Code:
A=P[(1+(r/n)[SUP]nt[/SUP])-1]
     ______________
           (r/n)
How much would be saved at the end of six years.

Homework Equations


The Variables:
Code:
P=3000
R=.068
n=1
t=6
The Completed formula:
Code:
A=3000((1+(.068/1)^(1)(6))-1)
     _______________________
           (.068/1)
When i put this exactly into http://web2.0calc.com/ (because I am without a scientific calculator at the moment)

The Attempt at a Solution



My Final Answer Is: A=44102.945538271292235294118
Rounded To The Nearest dollar: A=$44103
The program I Am Submitting The Answer To Says, the answer is: A=$21352 rounded to the nearest dollar.

My question is why is my answer wrong, is it the calculator? do i have a parentheses out of place?


_____________________________________________________________________________
EDIT: fixed spelling errors and a few minor changes, none involving the math.
 
Last edited:
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  • #2
after about an hour of crying and an hour of raging that no1 would reply i figured out the mistake it was a parentheses
 
  • #3
So it was the missing parents around the (1)(6) factor right?
 
  • #4
nope, it wasn't, even tho that would have been another issue if my post was completely honest i actually multiplied them together before i put it in the calculator, the issue was the (1+(.068/1)^(1)(6)) should have been ((1+(.068/1))^((1)(6)))
 
  • #5
in other words, add the 1 to the fraction before the exponent
 
  • #6
yumito said:
...the issue was the (1+(.068/1)^(1)(6))
should have been ((1+(.068/1))^((1)(6)))


What I do to reduce the number of parentheses for that part in the
calculator display and make it relatively easier to read is type:


((1+0.068/1)^(1*6))
 
  • #7
well from my time spend in my programing classes i must have completely forgotten how to debug, i have become too reliant of others help and need to seriously look at the problem before asking for help. on the most basic level, there are more just remove the outter most set of parenthesis until you see the problem lol
 
  • #8
checkitagain said:
What I do to reduce the number of parentheses for that part in the
calculator display and make it relatively easier to read is type:


((1+0.068/1)^(1*6))

Why do you show division by 1 and multiplication by 1? Instead of 1 + .068/1, why not write 1.068? And instead of 1*6, why not write just 6?
 
  • #9
Mark44 said:
Why do you show division by 1 and multiplication by 1?
Instead of 1 + .068/1, why not write 1.068?
And instead of 1*6, why not write just 6?

I was emphasizing an intermediate step where it is common for some beginning
calculator users to enter a product incorrectly. I was allowing for a denominator
other than 1 and a larger product for the exponent by my example.**

For myself, I would actually enter it they way you asked about for
[i[that problem[/i], because I know that is even simpler and I can
do that in my head.



** Example:

P(1 + 0.068/12)^(12*17) is what I would type for a different example
with relatively more difficult arithmetic.
 

1. How do I calculate the annuity value at 6 years with a 6.8% annual compound interest rate?

To calculate the annuity value at 6 years with a 6.8% annual compound interest rate, you can use the following formula: A = P * ((1+r)^n - 1)/r, where A is the annuity value, P is the initial investment, r is the annual interest rate (in decimal form), and n is the number of compounding periods (in this case, 6).

2. Can I use a regular calculator to solve this problem?

Yes, you can use a regular calculator to solve this problem. Just make sure to input the values in the correct order and use the correct formula.

3. What is the difference between annual compound interest and simple interest?

Annual compound interest is calculated by adding the interest earned each year to the principal amount, while simple interest is calculated by multiplying the principal amount by the interest rate and the number of years. This means that with compound interest, your investment grows at a faster rate.

4. How do I convert the annual interest rate to a decimal form?

To convert the annual interest rate to a decimal form, simply divide the percentage by 100. For example, 6.8% would be converted to 0.068.

5. Is this calculation accurate for any type of annuity?

This calculation is accurate for a regular annuity, which has equal payments and compounding periods. For other types of annuities, such as annuities with varying payments or compounding periods, a different formula may be needed.

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