Does the integer k have at least three different positive prime factors?
(1) k/15 is an integer.
(2) k/10 is an integer.
For integer k to have atleast 3 different positive prime factors,
k = a.b.c, where a, b, c are prime numbers.
k/15 is an integer,
least value of k =15, which has two different prime factors 3 & 5. Insufficient.
k/10 is an integer,
least value of k =10 which has two different prime factors 2 & 5. Insufficient.
least value of k =30 which has two different prime factors 2, 3 & 5. Sufficient.
Answer is (C)
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