Respuesta :

Answer:

$421.10

Step-by-step explanation:

If the discount is 10%, that means the sale price is 90% of the original price.

Write the equation that represents that:

378.99 = 0.9x. Solve for x. Divide both sides by 0.9

378.99/0.9 = 421.10

That is the price before the discount and tax.