Carcass wrote:
For any integer n greater than 1, [n denotes the product of all the integers from 1 to n, inclusive. How many prime numbers are there between [6 + 2 and [6 + 6, inclusive?
(A) None
(B) One
(C) Two
(D) Three
(E) Four
[6 + 2 = (6)(5)(4)(3)(2)(1) + 2 =
2[(6)(5)(4)(3)(1) + 1], which is a multiple of
2. So, [6 + 2 is NOT prime
[6 + 3 = (6)(5)(4)(3)(2)(1) + 2 =
3[(6)(5)(4)(2)(1) + 1], which is a multiple of
3. So, [6 + 2 is NOT prime
[6 + 4 = (6)(5)(4)(3)(2)(1) + 2 =
4[(6)(5)(3)(2)(1) + 1], which is a multiple of
4. So, [6 + 2 is NOT prime
[6 + 5 = (6)(5)(4)(3)(2)(1) + 2 =
5[(6)(4)(3)(2)(1) + 1], which is a multiple of
5. So, [6 + 2 is NOT prime
[6 + 6 = (6)(5)(4)(3)(2)(1) + 2 =
6[(5)(4)(3)(2)(1) + 1], which is a multiple of
6. So, [6 + 2 is NOT prime
Answer: A
Cheers,
Brent