Q2. A laundry for car wash found that the average, for small size car, cleaning time is 5 mins in the morning and 6.5 mins at evening time when a sample of size 30 is taken at the two time periods. From the previous record, the laundry manager knew that car o1 = 2 mins for the morning shift and o = 2.5 mins for morning and evening repectively. Find the interval estimate for -2 with 90% confidence level.

Q: Suppose the population of IQ scores in the town or city where you live is bell-shaped, with a mean…

A: Solution-: Let, X= the population of IQ scores in the town Given: We find mean and standard…

Q: A sample of n = 6 scores has a mean of m = 5. one person with a score of x = 19 is added to the…

A: Sample size (n) = 6Mean(m)  =5

Q: One sample has n = 4 scores with SS = 100 and a second sample has n = 8 with SS = 140. What is the…

A:

Q: One sample of n=10 scores has a mean of 8 and a second sample of n= 5 scores has a mean of 2. if the…

A:

Q: The amount of time that people spent at Grover Hot Springs is normally distributed with a mean of 68…

A: Solution

Q: When we compute a standard deviation, we are trying to get a measure of the average distance of…

A: Let us understand better by assuming X1, X2, ...., Xn be n data points. Then,…

Q: An experiment was conducted to estimate the effect of smoking on the blood pressure of a group of 31…

A: The sample size is 31, sample mean is 9.1 and sample standard deviation is 5.3.

Q: Suppose the data represent the inches of rainfall in April for a certain city over the course of 20…

A: From the provided information,n = 20

Q: A random sample of 70 tires showed that the mean mileage per tire was 41,200 mi, with a standard…

A:

Q: Dwight wants to estimate the mean calorie content in beets with 90% confidence.  He believes that…

A: The population standard deviation, sigma is 17. The z-critical value for the 90% confidence interval…

Q: Suppose the rate of misprints in the printed text from a given publisher is three misprints per one…

A: The question is about discrete probability distribution.Introduction :1 ) Let, X be discrete random…

Q: Alan, a highway safety inspector, is concerned about the potential for accidents caused by boulders…

A: Given data μ = 565σ = 100normal distribution P(493<x<681) = ?

Q: A simple random sample of 64 observations was taken from a large population. The sample mean and the…

A:

Q: A teacher was interested in the number of times her students with ADHD interrupted her class each…

A: Given population mean is 25. average was µ = 27 and the standard deviation was σ = 1.2.  sample size…

Q: Suppose a friend tells you that the average length of trout caught in pyramid lake is u=19 inches.…

A: Given information Hypothesized mean = 19 Sample Standard deviation = 3.5 Sample mean = 18.6 Sample…

Q: Now, randomly select 4 samples of size n = 10 from the population. Record the samples below. As…

A: Given information: The data represents samples means of a randomly selected samples of size 10.

Q: In 1988, on the math SAT, the males taking the exam averaged about 500, while the females averaged…

A: From the provided information,

Q: Assume a normally distributed population with a mean = 90 and standard deviation = 12. Be sure to…

A: Given Mean=90 Standard deviations=12

Q: The distribution of average wait times in drive-through restaurant lines in one town was…

A: Given,mean(μ)=185standard deviation(σ)=11

Q: with M = 85 and s = 12 is transformed into z-scores. After the transformation, what are the values…

A: According to the sum, A sample with M = 85 and s = 12 is transformed into z-scores. M=sample mean=85…

Q: How would the P-value change? The P-value would remain unchanged because the variability measured by…

A: Hypothesis is an assumption that is being tested.

Q: Rick took a test that is known to produce normally distributed grades with a mean of 72 and a SD of…

A:

Q: There are two samples of children taken from a population. In the first sample, mean of age of 20…

A: Combined mean : To integrate two or more things into a single entity is to link them together.When…

Q: The first four deviations from the mean in a sample of n = 5 reaction times were .3, .9, 1.0, and…

A: It is given that, n=5 and  First four deviations from the mean for reaction time is 0.3,0.9,1.0,1.3…

Q: a standardize exam scores are normally distributed,in a recent year,the mean test scores was…

A:

Q: Use the formula to find the standard error of the distribution of differences in sample means,…

A: Given   Samples of size 40 from Population 1 with mean 3.7 and standard deviation 1.9 and samples of…

Q: After 5 points are added to every score in a distribution, the mean is calculated and found to be u…

A: After 5 points are added to every score in a distribution, the mean is calculated and found to be µ…

Q: In a sample distribution, a score of x = 21 corresponds to z = -1.00 and a score of x = 12…

A: The Z-score of a random variable X is defined as follows: Z = (X – µ)/σ. Here, µ and σ  are the mean…

Q: P3. Show that the mle of unknown standard deviation when the mean is known is different from the…

A:

Q: The mean of 15 sample IQ score of statistic instructors is 118. The sample standard deviation is 11.…

A: