Permutation and CombinationHard
Question
The number of divisors of apbqcrds where a, b, c, d are primes & p, q, r, s ∈ N, excluding 1 and the number itself, is:
Options
A.p q r s
B.(p + 1) (q + 1) (r + 1) (s + 1) - 4
C.p q r s - 2
D.(p + 1) (q + 1) (r + 1) (s + 1) - 2
Solution
Total number of divisors is
(p + 1) (q + 1) (r + 1) (s + 1) - 2
(p + 1) (q + 1) (r + 1) (s + 1) - 2
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