After another late night at the office, Daddy came to little son's  room just as Johnny was getting in bed.  Johnny asked, "Daddy how much do you get paid an hour?"  His Daddy replied, "I make $20 an hour ....... why do you ask Johnny?"  There was silence and then he asked, "Daddy, could you give me $10?"  As Daddy handed him the $10 he asked Johnny what the money was for.  Johnny excitedly replied,  "Thanks Daddy.....with the money I already had, now I have enough money to pay for an hour of your time so you can play with me."