Final answer:
The total balance of the two investments after 3 years will be $1323.41.
Step-by-step explanation:
To calculate the total balance after 3 years, we need to calculate the interest for both the simple interest and compound interest accounts. For Martin's mother's account, the total balance with simple interest will be $600 + ($600 × 0.0575 × 3) = $661.50. For Martin's dad's account, the total balance with compound interest can be calculated using the formula:
Total Balance = Principal × (1 + Interest Rate)^Time. Substituting the values, we get:
Total Balance = $600 × (1 + 0.0525)^3 = $661.91.
Therefore, the total balance of the two investments after 3 years will be $661.50 + $661.91 = $1323.41. Rounded to the nearest cent, the answer is $1323.41.