So, for this question, the first sentence in the question stem is not necessary?
---On the number line, the distance between x and y is greater than the distance between x and z. ---

Will

I wonder why the GMAC sets this kind of question, which tests more your conversion (multiply/divide) skill rather than your concept.

Right. Here are three ways you can use expect as a verb. Expect immediately before a verb: We expect to receive the new shoes tomorrow. Expect that before a clause with its own subject: We expect that the new shoes will arrive tomorrow. Expect before a noun and infinitive: We expect the new shoes t...