# Multiple Choice Questions about Counting, Permutation n Combination

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
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!

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

3×5=15
4. The permutation of k elements which are taken from n elements are provided, can be notated by …
A. kPn B. nPk C. kCn D. nCk E. n!/k!

5. The value of

A. 60 B. 30 C. 20 D. 15 E. 10

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

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

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!