Odds

• Odds are used in places where people gamble.
• They are the ratio of payoff to stake in gambling.
  • if you bet $1
  • the odds are 1 to 5,
  • you will be paid $5 if you win.
• Odds are normally express as
  • a to b
  • a : b
• Mathematically there are two forms of odds
  • Odds against an event E = $\frac{P(not E)}{P(E)}$
  • Odds in favor an event E = $\frac{P(E)}{P(not E)}$
• When listed in a place of legal gambling, odds are always given as odds against.
• Do lots of problems p 650
• Do problem 36