what is wrong here?

[allegansveritatem]

I came across the this in the problems in a section labeled: Problems for Discussion in the back of one of the chapters in my precalculus text. I keep getting an impossibly large answer when I work out formula. The parameters I am using are: 90000$ loan at .03 interest over 30 months with payments of 300$ per month. Here is the part of the problem I am asking about:


Here is one version of what I did with it:

 

[pka]

I came across the this in the problems in a section labeled: Problems for Discussion in the back of one of the chapters in my precalculus text. I keep getting an impossibly large answer when I work out formula. The parameters I am using are: 90000$ loan at .03 interest over 30 months with payments of 300$ per month. Here is the part of the problem I am asking about:
View attachment 15461

Here is one version of what I did with it:

Using \(\displaystyle \frac{{12(300){{\left( {1 + \frac{{.03}}{{12}}} \right)}^{12*2.5}}}}{{0.03}} \approx 12,994\) See here.
Notice that 30 mos. is 2.5 years & t is in terms of years not months.

 

[allegansveritatem]

Using \(\displaystyle \frac{{12(300){{\left( {1 + \frac{{.03}}{{12}}} \right)}^{12*2.5}}}}{{0.03}} \approx 12,994\) See here.
Notice that 30 mos. is 2.5 years & t is in terms of years not months.

I am sorry that I made a mistake in posting this: I started the post last night and then continued it just now 24 hours later so I forgot that I changed my data: I used the parameters: .12 for rate, 30 years for term, 12 for number of payments per year and 90000$ for principle. I will fix this now in the original post.

 

[Deleted member 4993]

Using \(\displaystyle \frac{{12(300){{\left( {1 + \frac{{.03}}{{12}}} \right)}^{12*2.5}}}}{{0.03}} \approx 12,994\) See here.
Notice that 30 mos. is 2.5 years & t is in terms of years not months.

I see (at that WA page)

\(\displaystyle \frac{{12(300){{\left( {1 + \frac{{.03}}{{12}}} \right)}^{12*2.5}}}}{{0.03}} \approx 129,334\) = 129,334

 

[pka]

O.K. here is a correction
\(\displaystyle \frac{{12(300)\left[ {{{\left( {1 + \frac{{.03}}{{12}}} \right)}^{12*2.5}} - 1} \right]}}{{0.03}}\approx~9334\)
SEE HERE

 

[allegansveritatem]

I see (at that WA page)

\(\displaystyle \frac{{12(300){{\left( {1 + \frac{{.03}}{{12}}} \right)}^{12*2.5}}}}{{0.03}} \approx 129,334\) = 129,334

Please look at my other thread of the same title that I posted just after this. This one is not right in any way. I messed it up big time.

 

[allegansveritatem]

O.K. here is a correction
\(\displaystyle \frac{{12(300)\left[ {{{\left( {1 + \frac{{.03}}{{12}}} \right)}^{12*2.5}} - 1} \right]}}{{0.03}}\approx~9334\)
SEE HERE

Please look at my other thread of the same title that I posted just after this. This one is not right in any way. I messed it up big time

 

[allegansveritatem]

Using \(\displaystyle \frac{{12(300){{\left( {1 + \frac{{.03}}{{12}}} \right)}^{12*2.5}}}}{{0.03}} \approx 12,994\) See here.
Notice that 30 mos. is 2.5 years & t is in terms of years not months.

Please look at my other thread of the same title that I posted just after this. This one is not right in any way. I messed it up big time