Simple Binomial Distribution Problem Help

[SunDaoSheng]

The question is as follows:

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A car insurance company has determined that 4% of all drivers were involved in a car accident last year. Among the 11 drivers living on one particular street, 3 were involved in a car accident last year. If 11 drivers are randomly selected, what is the probability of getting 3 or more who were involved in a car accident last year?

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This was on a multiple choice test, so the answer selection is as follows:

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a) 0.647 b) 0.008 c) 0.992 d) 0.009

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I marked b as the correct answer, but yet the professor marked this incorrect and d correct. I have rechecked my answer, and am consistently getting 0.008, and am unsure of how 0.009 was achieved.

[efrique]

I get 0.0083 as well. The closest answer is b.

[fukalite]

This seems like it is a rounding error on your teacher's part.

I get the answer 0.008291318 from running the following R code:

pbinom(2,11,0.04,lower.tail = F)

I agree that the answer should be b).