Question 1085611
Use the binomial distribution formula
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p = 0.40, n = 300, r varies  from 0 to 124
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Probability (P) ( r successes out of 300 ) = 300Cr * (0.40)^300 * (1-0.40)^(300-r)
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Note 300Cr = 300! / (r! * (300-r)!)
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then sum the P(r)'s
:
fortunately there are binomial distribution calculators, therefore
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P ( 124 or fewer deer are infected ) = 0.7030 approximately 0.70 or 70%
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answer is B.
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