Based on published odds at 
    http://www.powerball.com/powerball/pb_prizes.asp
 
 At the time of writing, the jackpot was 82 million.
 Below is the calculation of the expected winnings for a $1 ticket.
 
 3/61.74 + 4/123.5 + 7/787.2 + 7/359 + 100/13644.24 + 100/19030.12 + 10/723 + 200/5138 + 82/195 = 0.595
    or 59.5 cents per $1 ticket.