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Ten points are plotted on a plane. Find the number of straight lines obtained by joining these points if no three points are collinear - Mathematics and Statistics

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प्रश्न

Ten points are plotted on a plane. Find the number of straight lines obtained by joining these points if no three points are collinear

योग
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उत्तर

A line is drawn by joining 2 points from the given 10 points.

∴ number of straight lines

= 10C2

= `(10!)/(2!8!)`

= `(10 xx 9 xx 8!)/(2 xx 8!)`

= 45, if no three points are collinear.

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Properties of Combinations
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 3: Permutations and Combination - Exercise 3.6 [पृष्ठ ६५]

APPEARS IN

बालभारती Mathematics and Statistics 2 (Arts and Science) [English] Standard 11 Maharashtra State Board
अध्याय 3 Permutations and Combination
Exercise 3.6 | Q 13. (a) | पृष्ठ ६५

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