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प्रश्न
There are 10 points in a plane of which 4 are collinear. How many different straight lines can be drawn by joining these points.
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उत्तर
Number of straight lines formed joining the 10 points, taking 2 points at a time =
∴ Required number of straight lines =\[45 - 6 + 1 = 40\]
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संबंधित प्रश्न
Determine n if `""^(2n)C_3 : ""^nC_3 = 12 : 1`
Compute:
(i)\[\frac{30!}{28!}\]
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