Simple Interest Calculator for a 5% Rate - Help with Homework Statement

[lil.l3b91]

Homework Statement

Karl invested his savings in a short-term fund that was offering a simple interest rate of 5% p.a. The maturity value of the investment at the end of 300 days was $29,152.08.
a. Calculate the principal amount invested.

Round to the nearest cent
b. Calculate the interest earned during the period.

Round to the nearest cent

Homework Equations

p=I/rt
I=prt

The Attempt at a Solution

p=s(1+rt)
p=29,152.08(1+0.05*300/365)

 

[Mark44]

Homework Statement

Karl invested his savings in a short-term fund that was offering a simple interest rate of 5% p.a. The maturity value of the investment at the end of 300 days was $29,152.08.
a. Calculate the principal amount invested.

Round to the nearest cent
b. Calculate the interest earned during the period.

Round to the nearest cent

Homework Equations

p=I/rt
I=prt

The Attempt at a Solution

p=s(1+rt)
p=29,152.08(1+0.05*300/365)[/B]

No.
The $29,152.08 is the amount at the end of the term, not the original investment amount.
You are missing an important relevant equation: A = P(1 + rt).
A is the amount that includes interest, and P is the amount that is invested at the beginning.

 

[WWGD]

Shouldn't there be an exponential there somewhere?

 

[Ray Vickson]

No.
The $29,152.08 is the amount at the end of the term, not the original investment amount.
You are missing an important relevant equation: A = P(1 + rt).
A is the amount that includes interest, and P is the amount that is invested at the beginning.

No: it is simple, not compound interest.

 

[Mark44]

You are missing an important relevant equation: A = P(1 + rt).

No: it is simple, not compound interest.

The formula I wrote (above) is for simple interest.

 

[Ray Vickson]

The formula I wrote (above) is for simple interest.

Sorry: I thought I was replying to WWGD in Post #3, but somehow the system linked me to the wrong message.

 

[Mark44]

Sorry: I thought I was replying to WWGD in Post #3, but somehow the system linked me to the wrong message.

I suspected that was the case.

 

[WWGD]

Yes, my bad, I misread.