Verified Answer :

So,

To find the sales tax rate, we just need to divide the tax amount by the sale price.

\(\frac{21}{350}\)

Simplify the fraction.
\(\frac{3*7}{2*5*5*7}\)

\(\frac{3}{2*5*5} = \frac{3}{50} = \frac{6}{100}\)

The sales tax was 6%.