Alice is given 100 free raffle tickets Each ticket has a 10

Alice is given 100 free raffle tickets. Each ticket has a 10 percent probability of winning $1.

What is Alice expected winning?

What is the standard deviation of Alice

Given:

Expected winning = n * p

Expected winning = 100 *0.10 = 10

Standard deviation = sqrt(n*p*(1-p))

Standard deviation = sqrt(100 *0.10 *0.90)

Standard deviation = sqrt(9)

Standard deviation = 3