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7001ENG: Research Methods for Engineers- Statistics Assignment Help
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Internal Code: TOA56
(a) Show a dot plot of the data with both low and high temperature tensile strength values in the same graph.
(b) Does it appear as if curing temperature has an influence on tensile strength, based on the plot? Comment further.
3. (5 marks) Large earthquakes with a magnitude greater that 6.0 occur rarely but smaller earthquakes are quite common. The following measurements were recorded in one month for a country:
1.5, 2.5, 3.1, 2.1, 2.5, 1.1, 3.2, 2.5, 1.1, 1.7, 1.9, 3.2.
Find the sample size, the mean, median, mode and midrange of the data.
4. (3 marks) Identify the statements below as TRUE or FALSE. If FALSE, explain.
(a) A variable is a characteristic of interest about each individual element of a population or sample.
(b) A population is the complete collection of individuals or objects or events whose properties are to be analysed.
5. (5 marks) Consider a family of three children. Find the probability that this family has exactly three girls. Use a tree diagram to show the possible outcomes.
6. (3 marks) Identify the POPULATION and the VARIABLE of interest in the below statements:
(a) “A study showed that 2% of the computer memory chips manufactured by an engineering company are usually defective.”
(b) “A study showed that the average salary for engineers aged 24-35 in Australia is AU$ 65,000.00 per year.”
7. (5 marks) An electrical firm manufactures light bulbs that have a length of life that is approximately normally distributed with a standard deviation of 40 hours. If a sample of 30 bulbs has an average life of 780 hours, find a 96% confidence interval for the population mean of all bulbs produced by this firm.
8. (10 marks) The manufacturer of a new fishing line claims this line has a mean breaking strength of 10 kg with a standard deviation of 0.6 kg. A random sample of 40 lines was tested and found to have a mean breaking strength of 9.8 kg. Use a 0.02 level of significance to test the hypothesis that ? = 10 kg against the alternative that ? ? 10 kg.
9. (6 marks) The annual salaries (in $100) of high school teachers employed at one of the high schools in Kent County, Michigan are listed below:
(a) Find the first quartile for these salaries, and interpret the result.
(b) Find the third quartile for these salaries, and interpret the result.
Statistics Assignment Help:
Task: 1. (3 marks) Identify the following statements as descriptive in nature, or as inferential: (a) “Based on a sample of 10,000 Americans, it is fair to say that 70% of all American are overweight.” (b) “80% of students in our Statistics class dislike true-false questions.” 2. (5 marks) The tensile strength of silicone rubber is thought to be a function of curing temperature. A study was carried out in which samples of 12 specimens of the rubber were prepared using curing temperatures of 20?C and 45?C. The data below show the tensile strength values in megapascals:
(a) Show a dot plot of the data with both low and high temperature tensile strength values in the same graph.
(b) Does it appear as if curing temperature has an influence on tensile strength, based on the plot? Comment further.
3. (5 marks) Large earthquakes with a magnitude greater that 6.0 occur rarely but smaller earthquakes are quite common. The following measurements were recorded in one month for a country:
1.5, 2.5, 3.1, 2.1, 2.5, 1.1, 3.2, 2.5, 1.1, 1.7, 1.9, 3.2.
Find the sample size, the mean, median, mode and midrange of the data.
4. (3 marks) Identify the statements below as TRUE or FALSE. If FALSE, explain.
(a) A variable is a characteristic of interest about each individual element of a population or sample.
(b) A population is the complete collection of individuals or objects or events whose properties are to be analysed.
5. (5 marks) Consider a family of three children. Find the probability that this family has exactly three girls. Use a tree diagram to show the possible outcomes.
6. (3 marks) Identify the POPULATION and the VARIABLE of interest in the below statements:
(a) “A study showed that 2% of the computer memory chips manufactured by an engineering company are usually defective.”
(b) “A study showed that the average salary for engineers aged 24-35 in Australia is AU$ 65,000.00 per year.”
7. (5 marks) An electrical firm manufactures light bulbs that have a length of life that is approximately normally distributed with a standard deviation of 40 hours. If a sample of 30 bulbs has an average life of 780 hours, find a 96% confidence interval for the population mean of all bulbs produced by this firm.
8. (10 marks) The manufacturer of a new fishing line claims this line has a mean breaking strength of 10 kg with a standard deviation of 0.6 kg. A random sample of 40 lines was tested and found to have a mean breaking strength of 9.8 kg. Use a 0.02 level of significance to test the hypothesis that ? = 10 kg against the alternative that ? ? 10 kg.
9. (6 marks) The annual salaries (in $100) of high school teachers employed at one of the high schools in Kent County, Michigan are listed below:
(a) Find the first quartile for these salaries, and interpret the result.
(b) Find the third quartile for these salaries, and interpret the result.