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Faculty of Economics and Business  
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Factorial Notation - Quiz 2   Last unanswered question  Question  Next unanswered question

Question 1 lion

Is the following statement True or False?
3! = 6.
a) True   b) False

 

Your answer is correct.
3! = 3× 2× 1 = 6.
Not correct. Choice (b) is false.
The statement is true
3! = 3× 2× 1 = 6.
Question 2 lion

Which of the following evaluates 4! correctly?
a) 4! = 10.    b) 4! = 24.
c) 4! = 32.    d) 4! = 120 .

 

Not correct. Choice (a) is false.
Try again, you have calculated 4 + 3 + 2 + 1 = 10.
Your answer is correct.
4! = 4× 3 ×2 × 1 = 24.
Not correct. Choice (c) is false.
Try again, you have not calculated 4 ×3 × 2× 1.
Not correct. Choice (d) is false.
Try again, this is 5!.
Question 3 lion

Which of the following correctly evaluates 7!.
4!
a) 7! = 210 .
4!    b) 7!
4! = 42.
c) 7!   7
4! = 4 .    d) 7!
4! = 1260.

 

Your answer is correct.
7!= 7 × 6× 5 = 210.
4!
Not correct. Choice (b) is false.
Try again, this is 7!
5! .
Not correct. Choice (c) is false.
Try again, you cannot cancel out factorial symbols.
Not correct. Choice (d) is false.
Try again, this is 7!
 4 .
Question 4 lion

Which of the following is the correct evaluation of  9!
6!3! .
a)  9!
6!3! = 168.    b) -9!-
6!3! = 20 160.
c) -9!- = 84 .
6!3!    d) -9!-= 1 .
6!3!  2

 

Not correct. Choice (a) is false.
Try again, have you divided by 3! or by 3?
Not correct. Choice (b) is false.
Try again, you have calculated --9!-.
6 × 3
Your answer is correct.
-9!-= 9-×-8×-7 = 84.
6!3!  3 × 2× 1
Not correct. Choice (d) is false.
Try again, you have forgotten the factorial symbol.
Question 5 lion

Consider ( )
 n  =  ---n!---.
 r     r!(n - r)!
Which of the following statements are correct? There is more than one correct answer.
a) (  )
  6  = 15 .
  4    b) ( )   ( )
 8  =  8  .
 3     5
c) (  )
  8  = 2.
  4    d) (  )
  5
  1  = 5.
e) ( )
 6
 3  = 18.    f) (  )
  9
  0 is not defined

 

There is at least one mistake.
For example, choice (a) should be true.
( )
 6  = 6-×-5= 15 .
 4    2 × 1
There is at least one mistake.
For example, choice (b) should be true.
Since n -(n - r) = r  we have (     )              (  )
   n    = ---n!----=   n .
  n- r    (n -r)!r!    r
There is at least one mistake.
For example, choice (c) should be false.
( )
 8  =  8!-=  8×-7×-6×-5-= 70.
 4     4!4!   4× 3× 2× 1
There is at least one mistake.
For example, choice (d) should be true.
( )
 5    -5!-
 1  = 1!4! = 5 .
There is at least one mistake.
For example, choice (e) should be false.
(  )
  6    -6!-  6-×5-×-4
  3  = 3!3! = 3 ×2 × 1 = 20 .
There is at least one mistake.
For example, choice (f) should be false.
Recall that 0! = 1.
Your answers are correct
  1. True. ( )
 6  = 6-×-5= 15 .
 4    2 × 1
  2. True. Since n -(n - r) = r  we have (     )              (  )
   n    = ---n!----=   n .
  n- r    (n -r)!r!    r
  3. False. ( )
 8  =  8!-=  8×-7×-6×-5-= 70.
 4     4!4!   4× 3× 2× 1
  4. True. ( )
 5    -5!-
 1  = 1!4! = 5 .
  5. False. (  )
  6    -6!-  6-×5-×-4
  3  = 3!3! = 3 ×2 × 1 = 20 .
  6. False. Recall that 0! = 1.