The lengths of human pregnancies can be described by a Normal model with a mean of 268 days and a standard deviation of 15 days.  In general, how long would a pregnancy last if it was in the 80th percentile for length of time?

Q: We notice a mean loss of 7 pounds in a sample of 11 dieters, with a standard deviation of three…

A: We first find the critical value for 95% confidence interval

Q: College students, in general, have a mean of 60 and a standard deviation of 8 on a measure of…

A: Solution-: Let, X= The college students have loneliness scores  Given: We find,

Q: A group of data has a mean of 69 with a standard deviation of 5. What is the probability of finding…

A: Given the mean= 69 and standard deviation = 5 So, z score of 61 is:

Q: The lengths of the songs available for download on a website are normally distributed, with a mean…

A: Obtain the percent of the songs available for download on the website. The percent of the songs…

Q: The reading speed of sixth-grade students is approximately normal, with a mean speed of 125 words…

A: Mean = 125 Standard deviation = 24

Q: A manufacturer of light bulbs finds that one light bulb model has a mean life span of 1025 h with a…

A:

Q: Suppose the average amount of apples per tree in a large orchard is 600 pounds with a standard…

A: Given, Population mean µx=600 pounds Population standard deviation σx=70 pounds a. Assuming that the…

Q: In another company, every worker received a 5% raise. How does this affect the mean salary? The…

A: Every worker received a 5%. The mean defines that the center or average of the data and it is…

Q: The speeds of all cars on the tollway was found to be normally distributed with a mean of 63 miles…

A: It is given that that µ=63 mile per hour. Obtain the standard deviation of the speeds of all cars:

Q: In a study about the life expectancy of 200 thirty-year old males, the mean is 65 and the standard…

A: Sample size(n)=200 Mean(μ)=65 Standard deviation(σ)=10  The proportion of the males who live past 75…

Q: The heights of men, in centimetres, are normally distributed with a mean of 175 and a standard…

A:

Q: The cholesterol levels of an adult can be described by a normal model with a mean of 188​mg/dL and a…

A: Obtain the percent of adults expect to have cholesterol levels over 200mg/dL. The percent of adults…

Q: A data set has a mean of 300 and a standard deviation of 40. What value would have a z-score of z =…

A: z-score of z = - 2 is -7.55 Reason: z-score of z = - 2=-2-meanstandard deviation=-2-30040=-7.55

Q: If a distribution has a mean of 50 and a standard deviation of 5, what value would be -1 standard…

A: Given, μ=50σ=5z=-1x=?

Q: If each score is increased by 25, what will be the mean and standard deviation of the distribution…

A: Given that  The distribution of raw scores on particular achievement test Mean = 500 Standard…

Q: Which graph shows a normal distribution of student heights with a mean of 170 cm and a standard…

A: Normal Curve :The following are the normal curve properties The normal curve is bell shaped with…

Q: The weights of miniature horses are roughly normally distributed with a mean of 230 pounds and…

A: Given : The weights of miniature horses are roughly normally distributed with a mean of 230 pounds…

Q: The gestation period for human births can be taken as normally distributed with a mean of 256 days…

A: Given: The gestation period for human births can be taken as normally distributed with a mean of 256…

Q: A data set has size of 40. How many observations lie within two standard deviations of either sides…

A: The 68-95-99.7% (Empirical) Rule: For a normal distribution, the empirical rule (68-95-99.7% Rule)…

Q: The mean weight of newborn Golden Retriever Puppies is 15.2 ounces, with a standard deviation of 1.3…

A: Mean = 15.2 standarsd derivation = 1.3 x=14.4 p(x)=(x-mean)/s.d =(14.4-15.2)/1.3 = -0.8/1.3

Q: A class has a average height of 68 inches and a standard deviation of 2 inches. What percent of the…

A: Let x be the height which follows normal distribution with mean 68, and standard deviation 2. The…

Q: A set of wrist watch prices are normally distributed with a mean of 76dollars and a standard…

A: From the provided information, Mean (µ) = 76 Standard deviation (σ) = 10 X~N (76, 10) Here X be a…

Q: the mean weight of a group of boys is 145 lb, with a standard deviation of 4lb. if the weights are…

A:

Q: A quantitative data set has size 40. At least how many observations lie within two standard…

A: Introduction: Suppose X is a random variable with expectation, μ and standard deviation, σ. Then,…

Q: A class has an average height of 68 inches and a standard deviation of 2 inches. Find each value,…

A: For the given data Mean μ = 68 inchesStandard deviation σ = 2 inches

Q: the length of a certain species of fish were found to be normally distributed. the mean length is 72…

A: Any assumption about the parameter or probability function is called a hypothesis. Given data are…

Q: The gestation period for human births can be taken as normally distributed with a mean of 266 days…

A: Given:

Q: Students at Roseville High School took an IQ test with a mean of 100 and a standard deviation of 15.…

A: GivenMean(μ)=100standard deviation(σ)=15

Q: Assume the cholesterol levels of adult American women can be described by a Normal model with a mean…

A: Given data,μ=182σ=23

Q: The mean life of a battery is 55 hours with a standard deviation of 6 hours. The manufacturer…

A:

Q: The Virginia Cooperative Extension reports that the mean weight of yearling Angus steers is 1152…

A: a) Consider that the mean and standard deviation of a random variable X are µ and σ, respectively.…

Q: During 1 week, an overnight delivery company found that the weights of its parcels were normally…

A: A normal distribution is called a standard distribution if; 1. 68% of the values of the random…

Q: In general, the larger the animal the longer the length of pregnancy. For the horse, for example,…

A: A z-score represents the position of a data point in terms of its distance from the mean when…

Q: The speeds of cars traveling on UK motorways are normally distributed with mean 96 kilometers per…

A: We have given that.   X~N( μ , ?^2 )   μ =96 , ? = 10   Z-score =( x - μ )/?

Q: The weights of men are normally with a mean of 172 pounds and a standard deviation of 29 pounds.…

A: Let X be the random variable from normal distribution with mean (μ) = 172 and standard deviation (σ)…

Q: Suppose the exam average in a class is 72% with a standard deviation of 3. What proportion of…

A: Given data: Average score = 72 % Standard deviation  = 3% To find: What proportion of students…

Q: A livestock company reports that the mean weight of a group of young steers is 1150 pounds with a…

A: μ=1150σ=87  =P1050<x<1250

Q: The mean life of a battery is 50 hours with a standard deviation of 6 hours. The manufacturer…

A:

Q: Based on daily measurements, Brenda's weight has a mean of 200 pounds with a standard deviation of…

A: We know that, Coefficient of variation = (SD/mean)*100 For Brenda Coefficient of variation =…

Q: The weights of miniature horses are roughly normally distributed with a mean of 230 pounds and…

A:

Q: The prices of all college textbooks follow a bell-shaped distribution with a mean of $108 and a…

A: HERE GIVEN FOR BELL SHAPED DISTRIBUTION  MEAN=$108 S.D=$21

Q: A livestock company reports that the mean weight of a group of young steers is 1180 pounds with a…

A: GivenMean(μ)=1180standard deviation(σ)=90

Q: the mean weight of a group of boys is 145 lb, with a standard deviation of 5lb. if the weights are…

A: We have to find correct answer..

Q: In a population of 100 male fruit flies, the mean abdomen length is 2.0 mm and the standard…

A: Given  μ=2 and σ=0.3 Use standardization as z=x-μσ

Q: a data set has a mean of 210 and a standard deviation of 40, what is the z- Score for a ralue of140…

A: We have given that  Mean =mu=210 , standard deviation(sigma)=40 and x=140 X~N(mu,sigma^2)…

Q: If the weight of fertilizer in a 40-pound bag is normally distributed with a standard deviation of…

A: Define  the Random Variable, X : Weight of fertilizer in the bag. X ~ N(40,0.52) Hence , the mean, µ…

Q: The weights of baby tortoises are approximately normally distributed with a mean of 25.6 ounces and…

A:

Q: The mean of 7 consecutive integers is 10. What is the standard deviation?

A:

Q: Some IQ tests are standardized to a Normal model, with a mean of 100 and a standard deviation of 16.…

A: Given,   Mean = 100 Standard deviation = 16