First off, how in the world am I suppose to know that. Even if you lived near me, I do not think I would even be looking at how high your grass was, unless it was more then a foot. I would probably notice that and tell you to mow it.
That being said, that question would be filed under an impossible question to answer correctly. As I could keep guessing. I could say it was 3 inches high. . . But knowing you, it probably was 11-12 inches high. That is just purely a guess though Since I have no facts or information to go by.
All in all an ok question. I think I will start rating questions, haha j/k.
Well, did you want to ask me something else? Impossible questions are fine, just not as likely to be correct. I will most of the time make up stuff too. Since that is all I can do with it.