1 Answer
Solution :-
Given:
Total number of officers = 4
Total number of jawans = 8
Total number of selection to be made is 6
(i) to include exactly one officer
Number of ways = (no. of ways of choosing 1 officer from 4 officers) × (no. of ways of choosing 5 jawans from 8 jawans)
= (4C1) × (8C5)
By using the formula,
nCr = \( \dfrac{ n!}{r!(n – r)!}\)
(ii) to include at least one officer?
Number of ways = (total no. of ways of choosing 6 persons from all 12 persons) – (no. of ways of choosing 6 persons without any officer)
= 12C6 – 8C6
By using the formula,
nCr = \( \dfrac{ n!}{r!(n – r)!}\)
= (11×2×3×2×7) – (4×7)
= 924 – 28
= 896 ways
The required no. of ways are 224 and 896.
Answered by Sakshi | 1 year agoRelated Questions
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