Question: 2017 Winter Final - 20
Consider a coin that comes up heads with probability 1/5 and comes up tails with probability 4/5.
You flip this coin twice, independently of each other. For each heads, you win \$100. For each tails, you win \$50.
What is the expected value $\mathbb{E}(X)$ of $X$?
What is the expected value $\mathbb{E}(X)$ of $X$?
(a)
120
(b)
140
(c)
100
(d)
80