Scientists have estimated that at least 10% of all stars host planets, and that at least 1% of all planets have similar temperatures as the earth.

Scientists have estimated that at least 10% of all stars host planets, and that at least 1% of all planets have similar temperatures as the earth. If we assume that on such a planet, there is one-in-a-million chance an alien civilization can emerge, how many alien civilizations should there be in our neighbor, the Andromeda Galaxy?