having a hard time setting this in the right formula.

an investment of $2500 is made at an annual simple interest rate of 5.5%. How much additional money must be invested at an annual simple interest rate of 8% so that the total interest earned is 7% of the total investment.

Question

having a hard time setting this in the right formula.

an investment of $2500 is made at an annual simple interest rate of 5.5%.  How much additional money must be invested at an annual simple interest rate of 8% so that the total interest earned is 7% of the total investment.

barrycarter · Answer

How far have you gotten?

anonymous · Answer

I have gotten as far as reading the problem and trying to plug it into the formula I=Prt but  I dont think that I am putting it in right because I dont get close to the same as the book