In: Statistics and Probability
1) A Texas oil drilling company has determined that it costs $25,000 to sink a test well. If oil is hit, the revenue for the company will be $500,000. If natural gas is found, the revenue will be $150,000. If the probability of hitting oil is 3% and of hitting gas is 6%, find the expected value of sinking a test well.
2) Assume that for the next heavyweight fight the odds of Mike Tyson winning are 15 to 2. A gambler bets $10 that Mike Tyson will lose. If Mike Tyson loses, how much can the gambler hope to receive?
Question (1)
There are three outcomes on sinking a well,
1. Oil is Hit
2. Natural Gas is found
3 If nothing is hit
The table below gives us the expected value
Scenario | Revenue | Revenue - Cost | Probability | Probability * (Revenue - Cost) |
Oil is Hit | 500000 | 475000 | 0.03 | 14250 |
Natural gas is found | 150000 | 125000 | 0.06 | 7500 |
If nothing is hit | 0 | -25000 | 0.91 | -22750 |
Probability * (Revenue - Cost) = -1000 |
Here the Expected value of sinking a test well = Probability * (Revenue - Cost) = -1000
Question (2)
For the next heavyweight fight the odds of Mike Tyson winning are 15 to 2
The formoa for convering odds ratio to probability is as below
Probability p = (Odds ratio) / (1 + odds ratio)
Here odds ration for Mike Tyson winning = 15/2
So Probability of Mike Tyson winning = (15/2) / (1+15/2)
= (15/2) / (17/2)
= 15/17
Probability of Mike Tyson losing = 1 - (15/17)
= 2/17
So odds of Mike losing tge fight is 2 to 15
Total return based on the number of odds = Stake * odds + Stake
Here he bets $10 that Mike tyson loses
So His total treturn will be = 10*(2/15) + 10
= (20/15) + 10
= 1.3333 + 10
= $11.3333
So The gambler hopes to receive $11.333