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A used car dealer has 30 cars and 10 of them are lemons (i.e.~ mechanically faulty used cars), and you don't know which is which. If you buy 3 cars, what is the probability that you will get at least one lemon?

User Ferbolg
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1 Answer

7 votes

Answer: Hence, the probability that he will get at least one lemon is 0.70.

Explanation:

Since we have given that

Number of cars = 30

Number of lemon cars = 10

Number of other than lemon cars = 30-10 = 20

According to question, he bought 3 cars,

we need to find the probability that you will get at least one lemon.

So, P(X≤1)=1-P(X=0)=1-P(no lemon)

Here, P(no lemon ) is given by


(20)/(30)* (20)/(30)* (20)/(30)=((20)/(30))^3

so, it becomes,


P(X\geq 1)=1-((20)/(30))^3=1-(0.67)^3=0.70

Hence, the probability that he will get at least one lemon is 0.70.

User Schalton
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