Question 1117991
What's the probability of drawing a black king?
There are two of them in a standard deck of 52 cards so,
{{{P(BK)=2/52=1/26}}}
So the complement or the probability of not drawing a black king is,
{{{P(NBK)=1-1/26=25/26}}}
Her expected earnings would then be,
{{{E=(1/26)(25)-(25/26)(2)}}}
{{{E=25/26-2(25/26)}}}
{{{E=-25/26}}}
So she should expect to lose about 96 cents each time she plays. 
She probably shouldn't play this game unless she likes to lose.