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Signals using exactly 3 flags out of 5 different flags number:
A120
B45
C60
D20
Answer & Solution
Correct answer: C. 60
1. The places offer 5, then 4, then 3 choices.
2. Multiply them.
3. The count is 60.
_Source: NCERT Class 11 Mathematics, Chapter 7, Permutations and Combinations._
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