Answer:
5. 66%
Step-by-step explanation:
Sales tax = $19.80
Cost of item before sales tax = $330
Cost of item after sales tax = 19.80+19.80 + 19.80+330
= $349.80
Sales tax rate
19.80349.80×100%5.66%\begin{lgathered}\frac{19.80}{349.80} \times 100\% \\ 5.66\%\end{lgathered}
349.80
19.80
×100%
5.66%
So rate of sales tax is 5.66%
