This is not a conditional sentence. My interpretation of this sentence would be that the writer is not referring to you (the reader) as someone who is actually going through Google's job interview process. The reader is not thought of as an actual or prospective interviewee in this scenario.
The sentence just states that "Knowing the answer will get you past this question in Google's interview process." In other words, thinking along those lines is what Google expects from its (potential) employees.
This sentence is not meant as a recommendation / reprimand for interviewees and therefore does not constitute a condition under which you can / cannot succeed in the interview. It just describes what kind of questions can be asked and what the correct answer is, mentioning more as a side note that if you happen to know it, you will score on this question.
If you rephrase this sentence as conditional, it will actually put the reader in the interveiw setting, which is not what the author is going for.
I read through all of the answers here, and I have to disagree with some of them. If I'm wrong, please don't cast stones at me, but point me to where I can read more.
My point is that you can't call every if-sentence a conditional sentence from a logical perspective. I see here examples of if-sentences with all sorts of mixture of tenses. Although I know about mixed conditionals, some of these examples don't seem to me as either "normal" or "mixed" conditionals. That's why a conditional mood was invented in English or many other languages: it's used to convey an idea of condition/consequence. You can't just use any tense you want in an if-sentence and hope it will retain it's conditional sense. On the contrary, you often lose this concept of logical condition or make it more vague and subtle. It still resembles an if-conditional, but it often makes the condition -> consequence sound less relevant.
If you knew the answer, you've passed the test.
I would say a condition is, of course, implied here, but the focus has been shifted from the condition to the fact of having passed the test with knowing the answer as an undoubted prerequisite, not a condition.
If you visited a Midwest farm last summer, you have seen what drought can do to crops.
To me, it means something more like those who visited a Midwest farm have seen... A visit to a Midwest farm is just an example of how you can see the power of drought, I don't see it as a condition.