Ex 7.4, 9 - In how many ways can a student choose a programme - Combination

  1. Chapter 7 Class 11 Permutations and Combinations
  2. Serial order wise
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Ex 7.4, 9 In how many ways can a student choose a programme of 5 courses if 9 courses are available and 2 specific courses are compulsory for every student? Hence, the student has to select 3 courses out of remaining 7 courses Here, n = 7 & r = 3 No of ways selecting 3 course out of 7 course = nCr = 7C3 = 7!/(3!(7 −3)!) = 7!/(3!(7 −3)!) = 7!/3!4! = (7 × 6 × 5 × 4!)/(3 × 2 × 1 × 4!) = (7 × 6 × 5 )/(3 × 2 × 1) = 35 ways

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  • Akshay Gaur's image
    Kha combination lgega or Kha permutations 
    Ye Kase pta chalta h 😤😤
    View answer
  • Dharan Sundar's image

    . In how many ways can a student choose a programme of 5 courses if 9 courses are available and 2 specific courses are compulsory for every student? 

    Why do 2 specific course not get added to answer 35

    View answer
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