For Mega Millions, the initial 5 balls are drawn from a pool of 70 balls, and the extra ball (called the Mega Ball) is drawn from a pool of 25. http://youinvoice.com/__media__/js/netsoltrademark.php?d=madesports.net%2Feos%25ed%258c%258c%25ec%259b%258c%25eb%25b3%25bc-%25eb%25ac%25b4%25ed%2595%259c%25ed%2595%259c-%25ea%25b0%2580%25eb%258a%25a5%25ec%2584%25b1%25ec%259d%2598-%25ec%2584%25b8%25ea%25b3%2584%2F