'Three' in the Bible

Now there were standing there six stone water-vessels, according to the purification of the Jews, holding two or three measures each.

Jesus answered and said to them, Destroy this temple, and in three days I will raise it up.

The Jews therefore said, Forty and six years was this temple building, and thou wilt raise it up in three days?

Why was this ointment not sold for three hundred denarii and given to the poor?