Competency Evaluation on Understanding
Instructions: Choose the one correct answer (time 15 minutes).
1. 5! Has the same mmeaning with …
A. 5² C. 5∙4 E. 5∙4∙3∙2∙1
B. 5∙10⁵ D. 5∙4∙3
Answer: E, Explanation:
This operator “!” is factorial.

2. 11! Can be written to be …
A. 11∙10∙10! C. 11∙10∙9! E. 13∙12∙11!
B. 11∙9∙7! D. 11∙12∙13!
Answer: C, Explanation:

n!=n∙(n-1)∙(n-2)!
11!=11∙10∙9!3. An event can occur in three ways, then is followed by other event which can occur in 5 ways. The number of ways the two events occur =…
A. 2 B. 8 C. 10 D. 15 E. 20
Answer: D, Explanation:

3×5=154. The permutation of k elements which are taken from n elements are provided, can be notated by …
A. _kP_n B. _nP_k C. _kC_n D. _nC_k E. n!/k!
Answer: B Explanation:

5. The value of

A. 60 B. 30 C. 20 D. 15 E. 10
Answer: D, Explanation:

6. ₇P₃=⋯
A. 7!/3! B. 7!/4! C. 7!/(4!∙3!) D. 4!/7! E. 3!/7!
Answer: Explanation:
This operator “P” is permutation.

7. The value of ₅P₂ is equal to …
A. 60 B. 20 C. 10 D. 7 E. 3
Answer: B, Explanation:

8. The number of permutation of letters in word of OLALA =…
A. 5!/2! B. 5!/3! C. 5!/(2!∙2!) D. 5!/(2!∙3!) E. (3!∙2!)/5!
Answer: C, Explanation:
Remember permutation with repetition item(s).

9. The combination of 3 elements which is taken from 7 elements provided is equal to =…
A. 7!/3! B. 7!/4! C. 4!/3! D. 7!/(3!∙4!) E. 7!/(3!∙2!)
Answer: D, Explanation:

10. In a bag, there are 8 marbles in different colors. If 3 marbles are taken at the same time then the number of ways to take it =…
A. ₈P₃ B. ₃P₈ C. ₈C₃ D. ₃C₈ E. 8!/3!
Answer: C, Explanation:
There is no sequence. Use combination.