Stastics

43 results

maths-stastics

Find the mean for the following data variable=4,6,8,10,12 freqency=4,8,14,11,13

stastics

For each of the following confidence intervals, indicate how much of the distribution would be placed in the cutoff region for a two-tailed test from 80%, 85% and 99%

stastics

A population has mean 53 and standard deviation 12. Calculate the mean of x bar for a random sample of size 10.

Stastics

average for all football teams was an 86 with variance of 16. the buckeyes program over the last 16 year was a 93. is there sufficient proof at the .05 level of significance to say buckeyes were higher than everyone else.

stastics

Following are the speeds of 40 cars clocked by radar on a particular road in a 35-mph zone on a particular afternoon: 30, 36, 42, 36, 30, 52, 36, 34, 36, 33, 30, 32, 35, 32, 37, 34, 36, 31, 35, 20, 24, 46, 23, 31, 32, 45, 34, 37, 28, 40, 34, 38, 40, 52, 31, 33, 15, 27, 36, 40 ...

stastics

The first clzxx in a relative frequency table is 50-59 and the corresponding relative frequency is 0.2. What does the 0.2 value indicate?

stastics

Salaries of 31 college graduates who took a course in college have a mean, x of 66,700 a standard deviation , o of 17,120, construct a 90% confidence interval for estimating the population mean u.

stastics

Assume that a random sample is used to estimate a population proportion p. Find the margin of error E corresponds to the given statistics and confidence level. 90% confidence, the sample size is 1457, of which 30% are successes.

STASTICS

If the median home price in your area has decreased in your area in the last 2 years, how does this differ from the mean price in your area? Please explain why and include examples.

stastics

If 1.5% of the bolts made by an automotive factory are defective, what is the probability that in a shipment of 200 bolts, there are 6 defective bolts? Place your answer, rounded to four decimal places, in the blank.

Stastics

Bank of Connecticut estimated that balance on credit cards have follows Normal Distribution mean $845 with standard deviation $270. Calculate probability that balance on a single credit card is greater than $750

Stastics

If the population standard deviation is Ợ=8, how large a sample is necessary to have a standard error that is a. Less than 4 points? b. Less than 2 points? c. Less than 1 point?

stastics

johns runs a computer software store.he counted 128 people who walkrd by his store in a day , 60 of whom came into the store, of the 60 only 21 brought something in the store.estimate the prob that that a person who walks by the storeenter the store .round your answer to the ...

Stastics

An employer claims that full time employees have a mean income of $35,000. A sample of 200 employees were considered. Their mean salaray was $34,000. POP sd of $4,000. Does her claim seem reasonable at at 0.05 significance level?

stastics

solving problem the chicago public school system has about 680 schools about 130 of the schools will be closed. if the five schools are chosen at random find the probability that at least three of them willl be closed

stastics

Imagine that you have 10 CDs and 10 envelopes on a table before you; each CD and each envelope are labelled with a number such as 7 or 10. If you randomly put the CDs into the envelopes provided, what is the probability of matching only one CD into the wrong envelope?

Statistics

Given the following null hypothesis, give an example of a Type II error. Ho: There is no difference in the level of understanding of this chapter between students who have previously taken a statistics course and students who have not previously takn a stastics course.

Stastics

USA snapshot presented a bar graph depicting business travelers’ impression of wait times in airport security lines over the past 12 months. Statistics were derived from Travel Industry Association of American Business Traveler Survey of 2034 respondents. Could this be a ...

Stastics

A doctor at a local hospital is interested in estimating the birth weight of infants. How large a sample must she select if she desires to be 98% confident that the true mean is within 2 ounces of the sample mean? The standard deviation of the birth weights is known to be 5 ...

stastics

The value of “t” will increase as the standard deviation of the difference _____ and the difference between means ____. a. increase; decreases b. increases; increases c. decreases; decreases d. decreases; increases e. None of the above. Wouldn't this answer be either A or ...

stastics

Approimately 10.3% of American high school students drop out of school before gradution. Choose 10 students entering high school at random. Find the probability that (Assume binomial distribution): a. Exactly two drop out b. At least 7 graduate c. All ten stay in school and ...

stastics

I'm having a hard time with question, can someone help me? A random sample of medical files is used to estimate the proportion p of all people who have blood type B. If you have no preliminary estimate for p, how many medical files should you include in a random sample in ...

stastics- correlation and regression

for the table that follows: answer the following questions: x y 1 -1/4 2 -1/2 3 -3/4 4 ? * would the correlation between x and y in the table show above be positive or negative? i think that it would be negative, i am not sure that is correct? * find the value of y in the ...

Stastics

Look again at the distribution of ages in Problem before. : 2.0 points Each part is worth 1 point. a) About what percent of the people were in their thirties? Round your answer to one decimal place. unanswered b) A common (though not universal) definition of "senior citizen" ...

Stastics

A researcher wanted to test the effect of a new drug on reducing blood pressure. In the study, there were 35 participants. The researcher measured the participants’ blood pressure before and after the drug was administered. If we want to compare the mean blood pressure from ...

Quantitative, stastics and business

The distribution of annual earnings of all bank tellers with five years of experience is skewed negatively. This distribution has a mean of Birr 15,000 and a standard deviation of Birr 2000. If we draw a random sample of 30 tellers, what is the probability that their earnings ...

Stastics

To help consumers assess the risks they are taking, the Food and Drug Administration (FDA) publishes the amount of nicotine found in all commercial brands of cigarettes. A new cigarette has recently been marketed. The FDA tests on this cigarette yielded mean nicotine content ...

stastics

Practice Problem #16 pg. 307: A researcher theorized that people can hear better when they have just eaten a large meal. Six individuals were randomly assigned to eat either a large meal or a small meal. After eating the meal, their hearing was tested. The hearing ability ...

Stastics

In a statistical hypothesis test, how is the rejection region impacted when α, the level of significance, is increased? a.The answer depends on the value of β b.The size of the rejection region decreases c.The size of the rejection region increases d.The rejection ...

Quantitative, stastics and business

A company has three machines A, B and C which all produce the same two parts, X and Y. of all the parts produced, machine A produces 60%, machine B produces 30%, and machine C produces the rest. 40% of the parts made by machine A are part X, 50% of the parts made by machine B ...

Stastics

Suppose cars arrive at Burger King's drive-through at the rate of 20 cars every hour between 12:00 noon and 1:00 pm. A random sample of 40 one-hour periods between 12:00 noon and 1:00 pm is selected and has 22.1 as the sample mean number of cars arriving. (a) Why is the ...

Stastics

When we convert x-value to z- score and use Standard Normal distribution, which of the following statements is true? a) The mean of z-score is zero and standard deviation of the z-scores is the same as the standard deviation of original data b) The mean and standard deviation ...

Stastics

Which of the following descriptions of confidence intervals is correct? (Select all that apply) a. If a 95% confidence interval contains 0, then the 99% confidence interval contains 0 b. If a 99% confidence interval contains 0, then the 95% confidence interval contains 0 c. If...

Stastics

Can someone help me and let me know if what I have solved is correct. A researcher randomly surveyed 300 high school seniors and determined 225 stated they drive a car to high school. We are interested in the population proportion of seniors who drive a car to high school. a. ...

stastics

A recent article in a computer magazine suggested that the mean time to fully learn a new software program is 40 hours. A sample of 100 first-time users of a new statistics program revealed the mean time to learn it was 39 hours with the standard deviation of 8 hours. At the 0...

Stastics

Imagine a researcher presented a null hypothesis that in a certain community, the average energy expenditure of residents is at least 2,100 calories per day. He randomly sampled 100 residents in that particular community. He computed a negative test statistic and the ...

math

What kind of math classes must you take to become a Biologist? What kind of math classes must you take to become a Geneticist? I'm not a biologist, but I do know a little about math. I know there's a specialty in math called bio-stastics. I think that course requires at least ...

Stastics

The UMUC bookstore states the average textbook costs $119. A randomly selected sample of 26 new textbooks at the UMUC bookstore had a mean price of $123.45 and sample standard deviation of $15.23. Use a 0.05 significance level to test the claim that the mean price of textbooks...

stastics

A survey of drivers in the United States found that 15% never use a cell phone while driving. Suppose that drivers arrive at random at an auto inspection station. a. If the inspector checks 10 drivers, what is the probability that at least one driver never uses a cell phone ...

Stastics

In a study of proctored and non-proctored tests in an online course, researches obtained the data below: Group 1 (Proctored): 𝑛 = 30, 𝑥̅= 74.30, 𝑠 = 12.87 Group 2 (Non-proctored): 𝑛 = 32, 𝑥̅= 80.62, 𝑠 = 22.09 Use of 0....

Stastics

In a study of proctored and non-proctored tests in an online course, researches obtained the data below: Group 1 (Proctored): 𝑛 = 30, 𝑥̅= 74.30, 𝑠 = 12.87 Group 2 (Non-proctored): 𝑛 = 32, 𝑥̅= 80.62, 𝑠 = 22.09 Use of 0....

Stastics

Did I do this right and should i show more work? Listed below are body temperatures for four subjects measured at two different times in a day. Body Temperature (°𝐹) 𝑎𝑡 6 𝑎𝑚: 98.0,97.0,98.6,97.4 Body Temperature (°𝐹) 𝑎...

stastics

a car dealer estimates that they sell two cars on average per week. they only have space in their showroom for 4 cars. if stock replacement cannot take place within a week, what is the probability assuming that weekly car sales follow a poisson distribution that, the dealer ...

Pages

  1. 1