Greetings!
Answer:
$104
Explanation:
First, you need to find the total price of everything:
50 + 20 + 30 = 100
Now, as 100 = 100% of the price, imagine the 4% tax as an addition to this:
100 + 4 = 104
So you need to find what 104% of 100 is, this can be done using the percentage formula:
amount x

Plug the values into this
100 x

100 x 1.04 = $104
So the total price including the sales tax would be $104!
Hope this helps!