If 'n' objects are arranged in a row then number of ways of selecting three of these objects

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Gujarati

Hindi

6.Permutation and Combination

normal

If $'n'$ objects are arranged in a row then the number of ways of selecting three of these objects so that no two of them are next to each othe

A

${}^{n - 2}{C_3}$

B

${}^{n - 2}{C_2}$

C

${}^{n - 3}{C_3}$

D

None

Solution

Number of ways of selection of $^{\prime} 3^{\prime}$

$=$ Number of ways to put 3 in $(n-2)$ gapes

$=^{n-2} C_{3}$

Standard 11

Mathematics

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