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According to a study, an average of six cell phone thefts is reported in San Francisco per day. Assume that the number of reported cell phone thefts per day in the city follow the Poisson distribution. What is the probability that four or five cell phones will be reported stolen tomorrow?

User Chomp
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1 Answer

6 votes

Answer:0.29

Explanation:

An average of six cell phone thefts is reported in San Francisco per day. This means our mean value, u = 6

For poisson distribution,

P(x=r) = (e^-u×u^r)/r!

probability that four cell phones will be reported stolen tomorrow=

P(x=4)= (e^-6×6^4)/4!

= (0.00248×1296)/4×3×2×1

= 3.21408/24=

0.13392

P(x=5)= (e^-6×6^5)/5!

= (0.00248×7776)/5×4×3×2×1

= 19.28448/120

= 0.1607

probability that four or five cell phones will be reported stolen tomorrow

= P(x=4) + P(x=5)

= 0.13392 + 0.1607

= 0.294624

Approximately 0.29

User MyStackRunnethOver
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