Question

数学期望的题目。。大神快来

A company makes electronic gadgets. One out of every 50 gadgets is faulty, but the company does not know which ones are faulty until a buyer complains. Suppose the company makes a $3 profit on the sale of any working gadget, but it suffers a loss of $80 for every faulty gadget because they have to repair the unit. What is the expected payoff per gadget produced? (No $ sign required ; answer with 2 decimals after the point)

Answer 1

生产一个损坏零件的概率为1/50,则生产一个完好零件的概率为1-1/50
期望E=（1-1/50）×3-1/50×80=67/80

Answer 2