Question
In how many ways can a squad of 10 people be selected
from 9 trainees and 5 supervisors such that the squad has at least 8 trainees?Solution
Case I: 8 trainees and 2 supervisors
Number of ways = 9C8 × 5C2 = 9 × 10 = 90 ways
Case II: 9 trainees and 1 supervisor
Number of ways = 9C9 × 5C1 = 1 × 5 = 5 ways
Total number of ways = 90 + 5 = 95 ways
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