# Problem #1599

 1599 Suppose $a$ and $b$ are single-digit positive integers chosen independently and at random. What is the probability that the point $(a,b)$ lies above the parabola $y=ax^2-bx$? $\textbf{(A)}\ \frac{11}{81} \qquad \textbf{(B)}\ \frac{13}{81} \qquad \textbf{(C)}\ \frac{5}{27} \qquad \textbf{(D)}\ \frac{17}{81} \qquad \textbf{(E)}\ \frac{19}{81}$ This problem is copyrighted by the American Mathematics Competitions.
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• Numbers involving pi should be written as 7pi or 7pi/3 as appropriate.
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• If the problem is multiple choice, enter the appropriate (capital) letter.
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