Tamil Nadu Board of Secondary EducationHSC Science Class 11

A trust has 25 members. How many ways 3 officers can be selected? - Mathematics

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Sum

A trust has 25 members. How many ways 3 officers can be selected?

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Solution

Number of members in the trust = 25

The number of ways of selecting 3 officers from 25 members is

= 25C3 

= `(25!)/(3! xx (25 - 3)!)`

= `(25!)/(3! xx 22!)`

= `(25 xx 24 xx 23 xx 22!)/(3! xx 22!)`

= `(25 xx 24 xx 23)/(3 xx 2 xx 1)`

= 25 × 4 × 23

= 2300

Concept: Combinations
  Is there an error in this question or solution?
Chapter 4: Combinatorics and Mathematical Induction - Exercise 4.3 [Page 186]

APPEARS IN

Tamil Nadu Board Samacheer Kalvi Class 11th Mathematics Volume 1 and 2 Answers Guide
Chapter 4 Combinatorics and Mathematical Induction
Exercise 4.3 | Q 11. (i) | Page 186

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