Fundamentals of Statistics 4th Edition solutions

Fundamentals of Statistics 4
On-Time Flights According to flightstats.com, American Airlines flights from Dallas to Chicago are on time 80% of the time. Suppose 15 flights are randomly selected, and the number of on-time flights is recorded. (a) Explain why this is a binomial experiment. (b) Find and interpret the probability th

Fundamentals of Statistics 4
The Empirical Rule The following data represent the weights (in grams) of a random sample of 50 M&M plain candies. (a) Determine the sample standard deviation weight. Express your answer rounded to three decimal places. (b) On the basis of the histogram drawn in Section 3.1, Problem 27, comme

Fundamentals of Statistics 4
Sneeze According to a study done by Nick Wilson of Otago University Wellington, the probability a randomly selected individual will not cover his or her mouth when sneezing is 0.267. Suppose you sit on a bench in a mall and observe peoples habits as they sneeze. (a) What is the probability that am

Fundamentals of Statistics 4
SMART Car The following data represent the miles per gallon of a random sample of SMART cars with a three cylinder, 1.0-liter engine. 31.5 36.0 37.8 38.4 40.1 42.3 34.3 36.3 37.9 38.8 40.6 42.7 34.5 37.4 38.0 39.3 41.4 43.5 35.5 37.5 38.3 39.5 41.5 47.5 Source: www

Fundamentals of Statistics 4
Manufacturing Steel rods are manufactured with a mean length of 25 centimeters (cm). Because of variability in the manufacturing process, the lengths of the rods are approximately normally distributed, with a standard deviation of 0.07 cm. (a) What proportion of rods has a length less than 24.9 cm

Fundamentals of Statistics 4
Chips Ahoy! Cookies The number of chocolate chips in an 18-ounce bag of Chips Ahoy! chocolate chip cookies is approximately normally distributed, with a mean of 1262 chips and a standard deviation of 118 chips, according to a study by cadets of the U.S. Air Force Academy. Source: Brad Warner and J

Fundamentals of Statistics 4
Statistics in the Media One of the more popular statistics reported in the media is the president's job approval rating. The approval rating is reported as the proportion of Americans who approve of the job that the sitting president is doing and is typically based on a random sample of registered vo

Fundamentals of Statistics 4
Blood Type A phlebotomist draws the blood of a random sample of 50 patients and determines their blood types as shown: (a) Construct a frequency distribution. (b) Construct a relative frequency distribution. (c) According to the data, which blood type is most common? (d) According to the data,

Fundamentals of Statistics 4
Height versus Head Circumference(Refer to Problem Height versus Head Circumference) A pediatrician wants to determine the relation that may exist between a child's height and head circumference. She randomly selects eleven 3-year-old children from her practice, measures their heights and head circumf

Fundamentals of Statistics 4
Sampling the Students The same community college from Problem 9 has 7656 students currently enrolled in classes. To gain the students opinions about an upcoming building project, the college president wishes to obtain a simple random sample of 20 students. He numbers the students from 1 to 7656. (a

Fundamentals of Statistics 4
Wendy's Drive-Through Fast-food restaurants spend quite a bit of time studying the amount of time cars spend in their drive throughs. Certainly, the faster the cars get through the drive-through, the more the opportunity for making money. QSR Magazine studied drive-through times for fast-food restaur

Fundamentals of Statistics 4
Square Footage of Housing The frequency distribution below represents the square footage of a random sample of 500 houses that are owner occupied year round. Approximate the mean and standard deviation square footage. Square Footage Frequency 0-499 5 500-999 17 1000-1499 36 1500-1999 121

Fundamentals of Statistics 4
Election Prediction Exit polling is a popular technique used to determine the outcome of an election prior to results being tallied. Suppose a referendum to increase funding for education is on the ballot in a large town (voting population over 100,000). An exit poll of 310 voters finds that 164 vot

Fundamentals of Statistics 4
Problem 27AYU Life Insurance A life insurance company sells a $250,000 1-year term life insurance policy to a 20-year-old female for $200. According to the National Vital Statistics Report, 58(21), the probability that the female survives the year is 0.999544. Compute and interpret the expected val

Fundamentals of Statistics 4
Cold Streaks Players in sports are said to have "hot streaks" and "cold streaks." For example, a batter in baseball might be considered to be in a slump, or cold streak, if he has made 10 outs in 10 consecutive at-bats. Suppose that a hitter successfully reaches base 30% of the time he comes to the p

Fundamentals of Statistics 4
Birthdays Exclude leap years from the following calculations and assume each birthday is equally likely: (a) Determine the probability that a randomly selected person has a birthday on the 1st day of a month. Interpret this probability. (b) Determine the probability that a randomly selected person

Fundamentals of Statistics 4
Watching Television The amount of time Americans spend watching television is closely monitored by firms such as A. C. Nielsen because this helps to determine advertising pricing for commercials. (a) Do you think the variable "weekly time spent watching television" would be normally distributed?

Fundamentals of Statistics 4
A Fish Story Ethan and Drew went on a 10-day fishing trip. The number of smallmouth bass caught and released by the two boys each day was as follows: Ethan 9 24 8 9 5 8 9 10 8 10 Drew 15 2 3 18 20 1 17 2 19 3 (a) Find the population mean and the range for the number of smallmo

Fundamentals of Statistics 4
Putting It Together: Playing Roulette In the game of roulette, a wheel consists of 38 slots numbered 0, 00, 1, 2, . . . , 36. (See the photo.) To play the game, a metal ball is spun around the wheel and is allowed to fall into one of the numbered slots. If the number of the slot the ball falls into

Fundamentals of Statistics 4
Credit Cards According to creditcard.com, \(29 \%\) of adults do not own a credit card. (a) Suppose a random sample of 500 adults is asked,"Do you own a credit card?" Describe the sampling distribution of \(\hat{p}\), the proportion of adults who own a credit card. (b) What is the probability