If x, y and z are positive integers, then
$$x^2y^3z^4$$
must be divisible by which of the following?
$$I.\ \ x^2+y^3+z^4$$
$$II.\ \ xy+xz$$
$$III.\ \ xyz+z$$
A. None
B. I only
C. I and II only
D. I and III only
E. II and III only
The OA is A.
I don't understand this PS question. Please, can any expert help me to solve it? Thanks.
If x, y and z are positive integers, then...
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Take the easiest possible case: x = 1, y = 1, and z = 1.swerve wrote:If x, y and z are positive integers, then
$$x^2y^3z^4$$
must be divisible by which of the following?
$$I.\ \ x^2+y^3+z^4$$
$$II.\ \ xy+xz$$
$$III.\ \ xyz+z$$
A. None
B. I only
C. I and II only
D. I and III only
E. II and III only
The OA is A.
I don't understand this PS question. Please, can any expert help me to solve it? Thanks.
$$x^2y^3z^4$$= 1.
$$I.\ \ x^2+y^3+z^4$$ --> 1 + 1 + 1 = 3. 1 is not divisible by 3. I is out.
$$II.\ \ xy+xz$$ --> 1 + 1 = 2. 1 is not divisible by 2. II is out.
$$III.\ \ xyz+z$$ --> 1 + 1 = 2. 1 is not divisible by 2. III is out.
So none of these statements needs to be true. The answer is A