Answer
$493.47
Work Step by Step
We know the following equation for continuously compounding interest:
$$A=Pe^{rt}$$
Where:
P is the principal.
A is the amount at the given time.
r is the rate, expressed as a decimal.
t is the time, in years.
Thus, we obtain:
$$A=400e^{.07*3} \\ A= 493.47$$