$3,000 is invested in an account paying 4% interest and twice that amount is invested at 6%. How do you write the expression that represents the amount of interest earned on the money invested at 6%?
Assumption: The interest given is the
Twice the amount is
Let the count of years be
Factoring out the
The 6% is 'spread' over each calculation cycle. There are 12 months in a year so instead of
Note that the count in years is