the specimen of copper wires drawn from a large lot have the follwing breaking strength (in kg. weight): 578,572,570,568,572,578,570,596,544 determine 95% confidence interval for the true mean breaking strength
Ans:
1 | 578 |
2 | 572 |
3 | 570 |
4 | 568 |
5 | 572 |
6 | 578 |
7 | 570 |
8 | 596 |
9 | 544 |
mean= | 572 |
std. dev= | 13.5 |
n=9
df=9-1=8
critical t value=tinv(0.05,8)=2.306
95% confidence interval for mean
=572+/-2.306*13.5/sqrt(9)
=572+/-10.38
=(561.62, 582.38)
the specimen of copper wires drawn from a large lot have the follwing breaking strength (in...
The breaking strengths of cables produced by a certain manufacturer have a standard deviation of 110 pounds. A random sample of 90 newly manufactured cables has a mean breaking strength of 1850 pounds. Based on this sample, find a 95% confidence interval for the true mean breaking strength of all cables produced by this manufacturer. Then compute the table below. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (If necessary, consult...
Past experience has indicated that the breaking strength of yarn used in manufacturing drapery material is normally distributed and that o = 2 psi. A random sample of 8 specimens is tested, and the average breaking strength is found to be 97 psi. Find a 95% two-sided confidence interval on the true mean breaking strength. Round the answers to 1 decimal place. Sus
Past experience has indicated that the breaking strength of yarn used in manufacturing drapery material is normally distributed and that σ = 7.2 psi. A random sample of nine specimens is tested, and the average breaking strength is found to be 95.5 psi. The 95% confidence interval for the true mean breaking strength is written as (A ; B). Find the value of B? round your answer to three digits.
Question 7 The mean breaking strength of yarn used in manufacturing drapery material is required to be more than 100 psi. Past experience has indicated that the standard deviation of breaking strength is 2.9 psi. A random sample of 9 specimens is tested, and the average breaking strength is found to be 100.6 psi. Statistical Tables and Charts (a) Calculate the P-value. Round your answer to 3 decimal places (e.g. 98.765). If a = 0.05, should the fiber be judged...
QUESTION 9 1 points Save Answer Past experience has indicated that the breaking strength of yarn used in manufacturing drapery material is normally distributed and that ơ-6.2 psi A randorm sample of nine specimens is tested, and the average breaking strength s found to be 7 psi The 95% confidence interval for the truc mean breaking strength is written as (A ; B). Find the value of A? round your answer to three digits. QUESTION 10 1 points Save Answer...
(16 points) Suppose the breaking strength of plastic bags is a Gaussian random variable Bags from company i have a mean strength of 8 kilograms and a variance of 1 kg2; Bags from company 2 have a mean strength of 9 kilograms and a variance of 0.5 kg' Assume we check the sample mean X1o of the breaking strength of 10 bags, and use X1o to determine whether a batch of bags comes from company 1 (null hypothesis Ho) or...
1. Suppose you have a sample of size 100 with mean 5 and standard deviation 2. Construct a 95% confidence interval for the population mean. 2. For a random sample of 50 measurements on the breaking strength of cotton threads, the mean breaking strength was found to be 210 grams and the standard deviation 18 grams. Calculate a 90% confidence interval for the true mean breaking strength of cotton threads of this type.
A sample of size 144 drawn from a large population has a sample mean of 47 and a sample standard deviation of 8. What is the? 95% confidence interval for the population? mean? Round to one decimal place as needed.
16-4
4. (16.12) A laboratory scale is known to have a standard deviation of σ 0.001 gram in repeated weighings. Scale readings in repeated weighings are Normally distributed, with mean equal to the true weight of the specimen. Three weighings of a specimen on this scale give 3.412, 3.416, and 3.414 grams. Data Set A 95% confidence interval for the true weight of this specimen is eBook 3.414 0.00113 3.414 0.00065 3.414 0.00196.
please answer all parts in detail :)
uppose the weights of parts in one lot has a normal distribution. Six parts were randomly drawn from this lot and weighed. Their weights were 21.6 oz. 22.4 oz. 21.4 oz. 20.2 oz. 22.0 oz 20.8 oz (a) (2 points] Compute the sample standard deviations of these six parts. (b) [4 points] Construct a 99% two-sided confidence interval for the true mean weight of all parts in this lot. (c) [4 points] Compute...