alleryThe number of ways to choose 3 books out of 5 (order does NOT matter) is:
A$60$ ways (using permutation 5P3)
B$10$ ways (using combination 5C3)
C$15$ ways
D$30$ ways
Answer & Solution
Correct answer: B. $10$ ways (using combination 5C3)
**Combinations (order doesn't matter):** 5C3 = 5!
/ (3! × 2!) = 120 / 12 = 10. Permutations (order matters): 5P3 = 5! / 2! = 60.
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