Questions from Applied Statistics

Q: Why might the number of calls received per minute at a fire

Why might the number of calls received per minute at a fire station not be a Poisson event?

Q: Software filters rely heavily on “blacklists” (lists of known

Software filters rely heavily on “blacklists” (lists of known “phishing” URLs) to detect fraudulent e-mails. But such filters typically catch only 20 percent of phishing URLs. Jason receives 16 phishi...

Q: The weekly demand for Baked Lay’s potato chips at a certain Subway

The weekly demand for Baked Lay’s potato chips at a certain Subway sandwich shop is a random variable with mean 450 and standard deviation 80. Find the value(s) of X for each event. Show your work. a...

Q: In a major league baseball game, the average is 1.

In a major league baseball game, the average is 1.0 broken bat per game. Find the probability of (a) no broken bats in a game; (b) at least 2 broken bats.

Q: In a certain microwave oven on the high power setting, the

In a certain microwave oven on the high power setting, the time it takes a randomly chosen kernel of popcorn to pop is normally distributed with a mean of 140 seconds and a standard deviation of 25 se...

Q: Dave the jogger runs the same route every day (about 2

Dave the jogger runs the same route every day (about 2.2 miles). On 18 consecutive days, he recorded the number of steps using a pedometer. The results were (a) Construct a 95 percent confidence int...

Q: At an outpatient mental health clinic, appointment cancellations occur at a

At an outpatient mental health clinic, appointment cancellations occur at a mean rate of 1.5 per day on a typical Wednesday. Let X be the number of cancellations on a particular Wednesday. (a) Justify...

Q: A sample of 40 CDs from a student’s collection showed a mean

A sample of 40 CDs from a student’s collection showed a mean length of 52.74 minutes with a standard deviation of 13.21 minutes. (a) Construct a 95 percent confidence interval for the mean. (b) Why mi...

Q: In a certain automobile manufacturing paint shop, paint defects on the

In a certain automobile manufacturing paint shop, paint defects on the hood occur at a mean rate of 0.8 defect per square meter. A hood on a certain car has an area of 3 square meters. (a) Justify the...

Q: Jim’s systolic blood pressure is a random variable with a mean of

Jim’s systolic blood pressure is a random variable with a mean of 145 mmHg and a standard deviation of 20 mmHg. For Jim’s age group, 140 is the threshold for high blood pressure. (a) If Jim’s systoli...