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Three Points from Grid Collinear

1250ApprenticeCombinatoricsGeometryProbability

AMC 10A · 2004 · Problem 5

A set of three points is randomly chosen from the grid shown. Each three point set has the same probability of being chosen. What is the probability that the points lie on the same straight line? [Asymptote diagram]

Answer choices

A
\frac{1}{21}
B
\frac{1}{14}
C
\frac{2}{21}
D
\frac17
E
\frac27
0 students attempted0% solvedRating 1250

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