A manufacturer suspects a difference in the quality of the spare narts he receives from two suppliers. He obtains the following data on the service life of random samples of parts from two suypliers. Standard Supplier Number in Sample Means Deviation 50 150 10 100 153 Test whether the difference between the two sample means is statisically significant at the 1% level of significance
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A manufacturer suspects a difference in the quality of the spare
narts he receives from two suppliers. He obtains the following
data on the service life of random samples of parts from two
suypliers.
Standard
Supplier
Number in Sample
Means
Deviation
50
150
10
100
153
Test whether the difference between the two sample means is
statisically significant at the 1% level of significance.
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