Count the crows
I don't know why a flock of crows is called "murder". This murder of crows (or are they rooks?) I saw had definitely not committed any murder but were, anyway, feasting on carrion.
When I approached them, the square root of half the number of crows took flight. Two other crows hopped to the side, and the remaining number of crows, that comprised eight-ninths of the whole flock, continued to feast undisturbed.
Can you tell me how many crows in all were there in the flock?