Factorial Quiz

Mathematics → Factorial Quiz

Factorial Multiple Choice Questions (MCQs) Page-1. The following quizzes are from factorial, permutations and combinations. Find answers and solutions to the questions at the bottom of the page.

Pages: 1 | 2

1. $0!=?$
(A) 0
(B) 1
(C) 10
(D) undefined

2. $n(n-1)\times...\times3\times2\times1=?$
(A) $n!$
(B) $^nC_r$
(C) $^nP_r$
(D) $n$

3. $7!=?$
(A) 70
(B) 120
(C) 720
(D) 5040

4. $5\times4!=?$
(A) 90
(B) 105
(C) 120
(D) 135

5. ${\Huge \frac{6!}{4!}=? }$
(A) 24
(B) 26
(C) 28
(D) 30

ANSWERS: FACTORIAL QUIZ
1. B
2. A
3. D
4. C
5. D

SOLUTIONS: FACTORIAL QUIZ

1. $0!=1$
By definition zero factorial is always equal to 1.

2. $n!=n(n-1)\times..\times3\times2\times1$
This is the definition of factorial. For example
$4!=4\times3\times2\times1$
$5!=5\times4\times3\times2\times1$

3. $7!=7\times6\times5\times4\times3\times2\times1=5040$

4. $5\times4!=5\times4\times3\times2\times1=120$