How do I use P=Irt when I have $1000 with an interest rate of 3% over 3 years to find how much I would earn at the end of 3 years?

Answer 1

Hi, Matthew!

I think you mean I=Prt, where I is interest, P is principal (what you put into the account at the start), r is the rate as a decimal, and t is time in years.

In this case, P=$1000 (a principal of $1000), r=.03 (3% as a decimal), and t=3 (3 years).

From here, simply, plug this information into the formula: I=(1000)(.03)(3)

According to the calculation, I (the interest earned) is $90.

Hope that helps!

Katie

Answer 2