Answer:
2658936 * [tex](\frac{14}{15})_{11} ^{12}[/tex]
Step-by-step explanation:
probability that the 20th person visiting the service station to purchase regular gasoline will be the 4th person to purchase regular gasoline without ethanol
probability of people who use regular gasoline without ethanol = 1/15 and will pay more ( $0.40) /gallon
The total number of customer in the service station (number of trials) X = 20
success ( r ) = 4
P = 1/15
The probability that the 20th person/customer visiting the station would be the 4th person to purchase regular gasoline without ethanol
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