In planning her retirement liza deposits some money at 3% interest with twice as much deposited at 4%. find the amount deposited at each rate if the total annual interest income is $1650.

Liza invested $15000 at 3% and $30,000 at 4%

Step-by-step explanation:

Let x be the amount invested by Liza at 3% interest then the amount she invested in 4% interest will be 2x.

We know that the compound interest with principal P is give By

, where n is the number of period.

Now, interest earned in 3% (in decimal 0.03) account in 1 year is given by:-

Similarly,  interest earned in 4% (in decimal 0.03) account in 1 year is given by:-

According to the question,

Also, 2x=2(15000)=30000

Therefore, Liza invested $15000 at 3% and $30,000 at 4% .