Answer:
$227.64
Explanation:
The relevant relations are ...
sales + tax = total
tax = 7% × sales
Using the second equation, we can write sales in terms of the tax as ...
sales = tax/0.07
Substituting this into the first equation gives ...
tax/.07 + tax = total . . . . . substitute for sales
tax(1/0.07 + 1) = total . . . . factor out tax
tax ((1 +.07)/.07) = total . . . simplify to a single fraction
Multiply by the inverse of this fraction:
tax = .07/1.07 × total = (7/107)($3479.64)
tax = $227.64