lightbulb wrote:
BUT:
According to their explanation, x = 2 is also correct, since according to them 0 is also a multiple of 5. I understand that when zero is divided by any number (other than 0), you get zero. But I am not sure if you can call zero a multiple of every number and I am wondering what GMAC's/GMAT Instructor's thought's are about this.
GMAC's definition of 'multiple' will be the same as that used universally in mathematics. What does it mean for 'x to be a multiple of y'? It means you can multiply y by an integer to get x. The multiples of 5 are:
...(-2)*5, (-1)*5, (0)*5, (1)*5, (2)*5, ...
i.e.
...-10, -5, 0, 5, 10, ...
In brief, zero is a multiple of every integer (and even of zero).
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