Re: If n is a multiple of 5 and n = p
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08 Apr 2021, 18:00
we are given that n is multiple of 5. n= p^2*Q where p and q are prime number
and asking which must be multiple of 25?
ok to make P or Q multiple of 25, one of them at least should equal to 25.
Similarly, n have to have at least one value of 5 to be multiple of 5.
(A) P^2 "can not be" why? ==> P could = 2 and q= 5 and hence 4 is not multiple of 25.
(B) Q^2 alone "can not be" for the same reason above.
(C) PQ still can not be. they could be 7*5 or 2*5 or even 5*5. and still we are not sure about the values of P and Q
(D) P^2*Q^2. This is the answer. if you apply the above, we will be getting 25 each time. which results in multiple of 25.
(E) p^3 q. can't be either.