Official Solution:
If positive integer \(x\) is divisible by 330, \(x\) must be divisible by which of the following?
I. \(\frac{x}{330}\)
II. \(330 - x\)
III. \(330 + x\)
A. I only
B. II only
C. III only
D. I and III only
E. I, II and III
Given: \(\frac{x}{330}=integer\)
Check the options:
I. \(\frac{x}{330}\). In this case \(\frac{x}{(\frac{x}{330})}=330=integer\). So, \(x\) must be divisible by \(\frac{x}{330}\).
II. \(330 - x\). In this case \(\frac{x}{330-x}\) is not necessarily an integer. For example, consider \(x=330\). We'd get \(\frac{x}{330-x}=\frac{330}{0}\), which is undefined.
III. \(330 + x\). In this case \(\frac{x}{330+x}\neq integer\) because the denominator is greater than the numerator (\(0 < \frac{x}{330+x} < 1\) ).
Answer: A