"Durable press" cotton fabrics are treated to improve their
recovery from wrinkles after washing "Wrinkle recovery angle"
measures how well a fabric recovers from wrinkles. Higher is
better. Here are data on the wrinkle recovery angle (in degrees)
for the some fabric specimens.
Permafresh | Hylite |
124 | 147 |
104 | 199 |
142 | 149 |
111 | 156 |
123 |
A consumer group suspects that there is a difference in recovery
from wrinkles after washing. Specifically, they want to test the
claim that there is a difference in recovery between using
Permafresh and Hylite. To investigate this, they identified the
mean recovery from wrinkles after washing by measuring the wrinkle
recovery angle in degrees for a sample of fabrics using Permafresh,
and a sample of fabrics using Hylite.
At the 5% level of significance, is there enough evidence to
conclude that there is a difference in wrinkle recovery angle
between Permafresh and Hylite?
It is often reasonable to conclude that measurements are normal in
distribution. So it is reasonable to assume the population of
wrinkle recovery angle is normal for both Permafresh and Hylite.
Also assume that the data represents a SRS(simple random sample) of
fabrics using Permafresh and Hylite.
3) Step 3: Assessment of Evidence. Find the pvalue
and upload an image of the normal curve with the test statistic
indicated and the correct area of the curve shaded. This shaded
area is the pvalue.
a) What is the pvalue? Use 4 decimal places.
b) Upload an image of the normal curve with the test statistic indicated and the correct area of the curve shaded. This shaded area is the pvalue.
Get Answers For Free
Most questions answered within 1 hours.