This assignment requires you to upload a Word file with the written report for Exercise 9.79. Full credit on this assignment requires that you also submit the Excel spreadsheets demonstrating your completion of Exercises 9.76, 9.77, and 9.78.
I WILL UPLOAD A FILE WITH THE QUESTIONS.
-
QuestionsQMB3250.docx
Questions
9.76:
An important quality characteristic used by the manufacturer of Boston and Vermont asphalt shingles is the amount of moisture the shingles contain when they are packaged. Customers may feel that they have purchased a product lacking in quality if they find moisture and wet shingles inside the packaging. In some cases, excessive moisture can cause the granules attached to the shingles for texture and coloring purposes to fall off the shingles, resulting in appearance problems. To monitor the amount of moisture present, the company conducts moisture tests. A shingle is weighed and then dried. The shingle is then reweighed and based on the amount of moisture taken out of the product, the pounds of moisture per 100 square feet are calculated. The company would like to show that the mean moisture content is less than 0.35 pound per 100 square feet. The file Moisture includes 36 measurements (in pounds per 100 square feet) for Boston shingles and 31 for Vermont shingles.
a. For the Boston shingles, is there evidence at the 0.05 level of significance that the population mean moisture content is less than 0.35 pound per 100 square feet?
b. Interpret the meaning of the p-value in (a).
c. For the Vermont shingles, is there evidence at the 0.05 level of significance that the population mean moisture content is less than 0.35 pound per 100 square feet?
d. Interpret the meaning of the p-value in (c).
e. What assumption about the population distribution is needed in
order to conduct the t tests in (a) and (c)?
f. Construct histograms, boxplots, or normal probability plots to
evaluate the assumption made in (a) and (c).
g. Do you think that the assumption needed in order to conduct the
t tests in (a) and (c) is valid? Explain.
9.77:
Studies conducted by the manufacturer of Boston and Vermont asphalt shingles have shown product weight to be a major factor in the customer’s perception of quality. Moreover, the weight represents the amount of raw materials being used and is therefore very important
to the company from a cost standpoint. The last stage of the assembly line packages the shingles before the packages are placed on wooden pallets. Once a pallet is full (a pallet for most brands holds 16 squares of shingles), it is weighed, and the measurement is recorded. The file Pallet contains the weight (in pounds) from a sample of 368 pallets of Boston shingles and 330 pallets of Vermont shingles.
a. For the Boston shingles, is there evidence at the 0.05 level of
significance that the population mean weight is different from
3,150 pounds?
b. Interpret the meaning of the p-value in (a).
c. For the Vermont shingles, is there evidence at the 0.05 level of
significance that the population mean weight is different from
3,700 pounds?
d. In (a) through (d), do you have to be concerned with the normal-ity assumption? Explain.
e. Interpret the meaning of the p-value in (c)
9.78:
The manufacturer of Boston and Vermont asphalt shingles provides its customers with a 20-year warranty on most of its prod-ucts. To determine whether a shingle will last through the warranty period, accelerated-life testing is conducted at the manufacturing plant. Accelerated-life testing exposes the shingle to the stresses it would be subject to in a lifetime of normal use in a laboratory setting via an experiment that takes only a few minutes to conduct. In this test, a shingle is repeatedly scraped with a brush for a short period of
time, and the shingle granules removed by the brushing are weighed (in grams). Shingles that experience low amounts of granule loss are expected to last longer in normal use than shingles that experience high amounts of granule loss. The file Granule contains a sample
of 170 measurements made on the company’s Boston shingles and 140 measurements made on Vermont shingles.
a. For the Boston shingles, is there evidence at the 0.05 level of
significance that the population mean granule loss is different
from 0.30 grams?
b. Interpret the meaning of the p-value in (a).
c. For the Vermont shingles, is there evidence at the 0.05 level of
significance that the population mean granule loss is different
from 0.30 grams?
d. Interpret the meaning of the p-value in (c).
e. In (a) through (d), do you have to be concerned with the normal-ity assumption? Explain.
9.79:
Referring to the results of Problems 9.76 through 9.78 con-cerning Boston and Vermont shingles, write a report that evaluates the moisture level, weight, and granule loss of the two types of shingles.
USEFUL NOTES FOR:
An important quality characteristic used by the manufacturer of Boston and Vermont asphalt shingles is the amount of moisture the shingles contain when they are packaged
Introduction
Asphalt shingles are one of the most popular roofing materials in North America. They’re durable and cost-effective, but like all products, they have their drawbacks. One of the most important quality characteristics used by the manufacturer of Boston and Vermont asphalt shingles is moisture content. Moisture content can cause the shingles to expand or contract after they are installed on a roof. If this happens during installation or later down the line with extreme weather conditions such as hail storms or high winds (which can damage any type of shingle), then your home may end up with leaks around flashings and nail penetrations, whereas overhead movement in a roof covered with shrinkable (expanding) shingles may result in cracks that allow water to enter the home—not what you want!
Moisture content can cause the shingles to expand or contract after they are installed on a roof.
Moisture content is the amount of water in a material. Moisture content is expressed as a percentage, and it’s determined by weighing a sample before and after exposure to air for 24 hours at 70 degrees F (21 degrees C). The lower the moisture content, the less likely your shingles will expand or contract after being installed on your roof.
The expansion or contraction of asphalt shingles affects how well these shingles hold up against severe weather conditions.
The expansion or contraction of asphalt shingles affects how well these shingles hold up against severe weather conditions. Asphalt shingles expand when they absorb moisture from the air, and this is what causes a problem for homeowners who live in areas that experience heavy rainfalls or snowfall.
Asphalt shingles will expand when exposed to moisture for longer periods of time. The amount of expansion depends on the amount of moisture in the shingle itself, but it can also be affected by temperature changes and other factors like wind velocity and barometric pressure levels. When this happens, cracks may form along where two pieces meet on your roof (if you live near water sources) which can lead to leaks from water damage caused by windy days outside where there’s been lots going on with Mother Nature lately!
A roof covered with shingles that shrink may develop leaks around flashings and nail penetrations, whereas overhead movement in a roof covered with shingles that expand may result in cracks that allow water to enter the home.
When a roof is covered with asphalt shingles, expansion and contraction is common. The shingles expand when heated by the sun and contract when cooled. When this happens during an extreme temperature change, it can cause leaks around flashings and nail penetrations in your home’s roof.
Overhead movement in a roof covered with an expanding type of asphalt may also cause cracks that allow water to enter your home through these spaces over time if you don’t repair them quickly enough or if they become too large for repair.
The amount of moisture the shingles have when you install them on your roof is crucial for their performance.
The amount of moisture the shingles have when you install them on your roof is crucial for their performance. If a shingle has too much moisture, it will expand and contract with changes in temperature; if it has too little, it may crack or break. The manufacturer of Boston and Vermont asphalt shingles keeps this in mind when designing their products—they make sure that each one contains just enough moisture so that they’re able to expand properly during installation (but not so much that they become brittle).
Conclusion
We hope that this article has given you a better understanding of how important the amount of moisture in your shingles is when they are installed. This information can help you make informed decisions about whether or not to install these products on your home and what type of roofing material would be best for your specific project.