To determine the rate, substitute the given values into the following equation:
where I is the amount of the interest, P is the principal amount, r is the rate, and t is the time in years.
Thus, we have:
Simplify the right side of the equation. Multiply 600 and 3.
Divide both sides of the equation by 1800.
Therefore, the rate is 0.025 or 2.5%.