Given:
John invest $5,000 in one account and $8,000 in an account paying 4% more in interest.
Total interest in one year = $1230
To find:
The rates of the investments.
Solution:
Let x% be the rate of interest on investment $5000.
Then, (x+4)% is the rate of interest on investment $8000.
Total interest is $1230. So,
Divide both sides by 130.
Now,
Therefore, $5,000 is invested at 7% and $8,000 is invested at 11%.