SOLUTION: 4. Strength tests carried out on samples of two yarns spun to the same count gave the following results: Number in sample Sample Mean Sample variance Yarn A 4 50 42 Yarn B 9

Question 517747: 4. Strength tests carried out on samples of two yarns spun to the same count gave the following results:
Number in
sample Sample
Mean Sample
variance
Yarn A 4 50 42
Yarn B 9 42 56
The strengths are expressed in pounds. Does the difference in mean strengths indicate a real difference in the mean strengths of the yarn?

Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Strength tests carried out on samples of two yarns spun to the same count gave the following results:
Number in sample Sample Mean Sample variance
Yarn A 4 50 42
Yarn B 9 42 56
The strengths are expressed in pounds. Does the difference in mean strengths indicate a real difference in the mean strengths of the yarn?
---------
Ho: uA - uB = 0
Ha: uA - uB is not 0 (claim)
-----
Sample mean: 50-42 = 8
---
I ran a 2SampleTtest on my TI-84 to get:
---
test stat: t = 1.9563
p-value: 0.0930
---
Conclusion: Since the p-value is greater than 5%,
fail to reject Ho at the 5% level of significance.
=============================
The test results do not support the claim.
============================================
Cheers,
Stan H.
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