Official Solution: Maya bought a framed print at an art gallery and paid a total of $96. If the $96 total consisted of the pre-tax price of the framed print plus sales tax on that pre-tax price, was the sales tax rate less than \(20\%\)? Let \(P\) be the pre-tax price of the framed print, and let \(T\) be the sales tax.
Since Maya paid $96 total:
\(P + T = 96\)
The question asks whether \(\frac{T}{P} < 0.20\).
(1) The pre-tax price of the framed print was less than $80.
This gives \(P < 80\). Since \(P + T = 96\), we have \(T > 16\). So:
\(\frac{T}{P} > \frac{16}{80} = 0.20\)
Therefore, the sales tax rate was not less than \(20\%\).
Sufficient.
(2) The sales tax Maya paid on the framed print was less than $19.20.
This is not enough.
For example, if \(T = 1\), then \(P = 95\), and the tax rate is \(\frac{1}{95}\), which is less than \(20\%\).
But if \(T = 18\), then \(P = 78\), and the tax rate is \(\frac{18}{78}\), which is greater than \(20\%\) because \(20\%\) of 78 is 15.6, and \(18 > 15.6\).
Not sufficient.
Answer: A