Difficulty: Easy
Correct Answer: 896
Explanation:
Introduction / Context:
We must count 6-person committees that include at least one officer. The complement (no officer) is easier to compute and subtract from the total committees possible.
Given Data / Assumptions:
Total people = 12 (4 officers + 8 jawans); committee size = 6.
Concept / Approach:
Total − (no officer). No-officer committees must be formed entirely from jawans.
Step-by-Step Solution:
Verification / Alternative check:
Summing by officer count (1 to 4) reproduces 896.
Why Other Options Are Wrong:
986, 886, 996 are off by ignoring the complement or miscomputing combinations.
Common Pitfalls:
Accidentally allowing 0 officers; arithmetic slips on C(12,6) or C(8,6).
Final Answer:
896
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