A grab bag contains 12 packages worth $.70 each, 15 packages $.40 cents each, and 25 packages worth $.30 each. What is the expected value if you have to pay $.50 to pick one package at random?
A.-$0.08
B.$0.01
C.$0.47
D.$0.00
i got 47 but i don't know it that is true can someone help me plz.
+6248 \(N=12+15+25 = 52\\ P[70c]=\dfrac{12}{52}=\dfrac{3}{13}\\ P[40c]=\dfrac{15}{52}=\dfrac{5}{13}\\ P[30c]=\dfrac{25}{52}\\~\\ E=70 \dfrac{3}{13}+40 \dfrac{5}{13}+30\dfrac{25}{52}-50 = -\dfrac{205}{26}\approx -\$0.08\)
.
+36915 I believ it just means you are PAYING MORE than the expected return....by 8 cents
