Ok, we need find first the sale tax and next we are going to add this to the price of the lamp, so let's do it.
The sale tax is 4% of the price of the lamp, so we are going to calculate it:
[tex]\frac{18.50}{100}\cdot4=0.74[/tex]Adding this we get:
[tex]0.74+18.5=19.24[/tex]The total price including sales tax is $19.24.
