Which of the following is an integer?
I. 9! / 6!
II. 9! / 8!
III. 9! / 7!5! Select the correct option:
A) I only B) II only C) III only D) I and II only E) I, II, and III
9!/6! = 9*8*7 which is an integer.   9!/8! = 9 which is an integer.   9!/7!5! = 9*8 / 5*4*3*2 = 3/5 which is not an integer.   The answer is I and II only.
<result>D</result>
Which of the following is an integer?
I. 9! / 6!
II. 9! / 8!
III. 9! / 7!5!