A commuter finds that she waits an average of 13.9 seconds at each of seven stoplights, with a standard deviation of 5.3 seconds. Find the mean and the standard deviation of the total amount of time she waits at all seven lights. What, if anything, did you assume? The mean time she waits at all seven lights is seconds. (Type an integer or a decimal.)

Q: a manufacturer claims that the mean lifetime of its fluorescent bulbs is 1050 hours. a homeowner…

A: Given n=40 Standard deviation =80 Xbar=1030 Level of significance=0.05 Mu0=1050

Q: the scores are normally distributed with a mean of 75 and a standard deviation of 9. What…

A: Note: As per the guidelines, only first three sub-parts (1., 2. and 3.) are solved here. Given data:…

Q: An officer of a certain agency claims that the mean monthly income of a family that lives in a…

A: The random variable monthly income of a family follows normal distribution. We have to write the…

Q: College Professors have incomes with a standard deviation that is more than $21,000. A recent study…

A:

Q: A quiz consists of 20 true or false questions. If the student guesses on each question what is the…

A: Solution: Let X be the number of correct answers and n be the number of questions. Since the…

Q: ant nursery, the owner thinks that the lengths of seedlings in a box sprayed with a new kind of…

A: Hypothesis testing is conducted for the parameters of the population, like population mean,…

Q: The prizes awarded to winning contestants on a long-running television show have a mean of $9,400…

A: We have to find mean and sd.

Q: The We Go Farther Tire Company advertises a tire that lasts for 80,000 miles. The mileage for the…

A:

Q: The annual income of residents in a county is $42,000 with a standard deviation of $10,000.  Under…

A: From the given information, the distribution of annual incomes is normally distributed with mean…

Q: Customers at a certain pharmacyspend an average of $54.40, with a standard deviation of $13.50.…

A: It is given that customers at a certain pharmacy spend an average of 54.40, with a standard…

Q: he mean life of a battery is 50 hours with a standard deviation of 7 hours. The manufacturer…

A: Given data,Mean μ=50standard deviation σ=7P(X<40)=?

Q: The 2018 Math Portion of the SAT score are normally distributed with a mean of 527 and a standard…

A: Empirical Rule: If a population has bell shaped distribution with mean µ and standard deviation σ ;…

Q: A sociologist found that in a sample of 50 retired men, the average number of jobs they had during…

A: Given that  Sample size=50 , Mean=6.9 Population Standard deviation=2.3

Q: In a PH modeling agency, a researcher wishes to see if the average height of female models is really…

A: Given,sample size(n)=32sample mean(x¯)=66.3sample standard deviation(s)=1.9degrees of…

Q: A nutritionist claims that the mean tuna consumption by a person is 3.1 pounds per year. A sample…

A: Solution: Let X be the tuna consumption by a person. From the given information, n=90, x-bar=2.9 and…

Q: If family income is positively skewed in a study with a standard deviation of $18000, knowing the…

A: Given information: The distribution of family income is positively skewed. The median family income…

Q: What is another name for the standard deviation of the variable x? What is the reason for that name?

A:

Q: A certain machine makes electrical resistors having a mean resistance of 50 ohms and a standard…

A: Let, X= resistance Given that X follows a normal distribution with mean=50 and standard deviation=4…

Q: A researcher finds that the mean income (in dollars per week) of a sample of people who live in a…

A: Given:

Q: In a mango farm of 250 trees, the mean harvest is 96.5 kilos of fruit per tree with a standard…

A: Given,sample size(n)=250mean(μ)=96.5standard deviation(σ)=8.4

Q: A recent survey was conducted to compare the cost of solar energy to the cost of gas or electric…

A:

Q: 95% of 80 night students scored between 70% and 80% on a quiz. If this data is normally distributed,…

A: Given: Total number of students n=80.             let X  denote the marks of students then,  X ~N(µ,…

Q: display of data to find the standar

A: Given,

Q: The average full-time faculty member in a post-secondary degree-granting institution works an…

A: In a bell shaped distribution, 68% items falls within one standard deviation of mean, 95% items…

Q: A manufacturer claims that a new design for a hands-free bluetooth device has increased the range to…

A: The following information is provided. Sample size, sample mean and sample standard deviation.…

Q: In an exam for a statistics class, the class average is 68 with a standard deviation 4. If a student…

A: Given mean μ= 68, standard deviation σ= 4 Let X: score of the students = 75

Q: A fast food restaurant sells hamburgers and chicken sandwiches. On a typical weekday the demand for…

A: The normal distribution:A continuous random variable X is said to follow normal distribution with…

Q: The amount of time a certain brand of light bulb lasts is normally distribued with a mean of 1500…

A:

Q: The number of incoming students at two campuses of a midwestern university have historically been…

A: Given that the main campus incoming class has a mean of 3,916 and a standard deviation of 375.…

Q: In a factory producing glasses, the weights of glasses are known to have a mean of 160 grams. It is…

A: By looking at a Z table we can conclude that Q1 and Q3 are each .6745 standard deviations from the…

Q: A light bulb manufacturer guarantees that the mean life of its brand of light bulb is 750 hours. If…

A: Given Information: Hypothesized value of the population mean is μ0=750 Sample size (n) = 36 Sample…

Q: Residents of an apartment send emails to the landlord on average, every 4 minutes, the standard…

A: Resident Sending an email to landlord  Mean 4 Standard Deviation 12 The landlord spends time…

Q: An e-reader has a one year warranty. The mean lifespan of the e-reader is 2.5 years, with a standard…

A: From the given information, the mean lifespan of the e-reader is 2.5 years and the standard…

Q: A survey of a number of the leading brands of cereal shows that the mean content potassium per…

A: Here we shall solve using Chebyshev’s theorem. Chebyshev's Theorem estimates the minimum proportion…

Q: The lengths of pregnancies in a small rural village are normally distributed with a mean of 260 days…

A:

Q: A manager is interested in finding the average number of sales per day at a sporting goods store. If…

A: Obtain the sample size. The sample size is obtained below as follows: The formula of sample size is,…

Q: is 6% is your standard deviation?

A: Given according to question Sample size(N)=? Confidence =95% Margin of error = 5% Now question says…

Q: According to a study, the salaries of registered nurse are normally distributed with a mean of 56310…

A: Given,mean(μ)=56310standard deviation(σ)=5038

Q: The annual precipitation amounts in a certain mountain range are normally distributed with a mean of…

A: Mean(µ) = 88Standard deviations (σ) = 10 X ~ N (µ, σ )= N(88, 10)

Q: Can you find the mean and the standard deviation?

A: To find the mean and standard deviation of the given data: Mean is the sum of observations divided…

Q: A nutritionist claims that the mean tuna consumption by a person is 3.3 pounds per year. A sample of…

A: (a) Let μ denotes the population mean tuna consumption. The claim of the test is that the mean tuna…

Q: A given set of data has a specific standard deviation. Describe what will happen to the standard…

A: Answer: The standard deviation of new data is remains same as original data. As a general rule, the…

Q: A student scored 76 on a general science test where the class mean and standard deviation were 82…

A: For Science x¯=82s=8x=76 z=x-x¯s=76-828=-0.75

Q: A statistical analysis of a very large sample of fully-assembled medical devices indicates that the…

A:

Q: Write down the formulas for the standard deviation of p.

A: Let sample size = n Sample proportion = p̄

Q: The president of a college wants to determine the mean number of units that college students take…

A: From the given information, the population standard deviation is 2.1 units, the confidence level is…

Q: A nutritionist claims that the mean tuna consumption by a person is 3.5 pounds per year. A sample of…

A: (a) Let μ is defined as the population mean tuna consumption by a person. The claim of the test is…

Q: for a population with a standard deviation of 4.2 and mean of 32.5, draw a bell shaped curve,…

A:

Q: Find the standard deviation for this data set. if a one goal hockey game was added to this data set,…

A: From the plot representing the number of goals scored per game, there are three games in which three…