#### Explanation:

To find the sales tax amount ($x$) on the price of the stereo system, we write the equation:

$x = 354 \times \frac{8.25}{100}$

$x = 29.205$

Rounding it off to $29.20$, we get the total price ($y$) as:

$y = 354 + 29.2$

$y = 383.2$