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Between​ 12:00 PM and​ 1:00 PM, cars arrive at a local​ bank's drive-thru at the rate of cars per hour ​( car per​ minute). The formula below from probability can be used to determine the probability that a car will arrive within t minutes of​ 12:00 PM. Use this information to answer the questions given below in parts ​(a)​(e).

User Janvb
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2 Answers

4 votes

Answer:

80/100=0.80

.8=1-e^-0.3t

.8+1=-e^-0.3t

1.8=-e^-.3t

t=5.36

Explanation:

User Alec Teal
by
8.3k points
5 votes

Complete question :

Between 12:00 PM and 1:00 PM, cars arrive at Citibank’s drive-thru at the rate of 6 cars per hour (0.1 car per minute). The following formula from statistics can be used to determine the probability that a car will arrive within t minutes of 12:00 PM. F(t)=1−e^−0.1t

Determine how many minutes are needed for the probability to reach 80%.

Answer:

16.09 minutes

Explanation:

Given the function :

F(t)=1−e^−0.1t

To attain 80% probability ; 80% = 0.8

0.8 = 1 - e^-0.1t

0.8 - 1 = - e^-0.1t

-0.2 = - e^-0.1t

Take the In of both sides

In(0.2) = In( e^-0.1t)

−1.609437 = - 0.1t

Divide both sides by - 0.1

−1.609437 / -0.1 = - 0.1t / 0.1

16.09 = t

Hence, the time it'll take will be 16.09 minutes

User Nadeem Qasmi
by
7.9k points
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