Posted by Kim on .
The University of Southern Mississippi currently uses GE brad fluorescent light bulbs that have a mean life of 900 hours. Sylvania clams that its new fluorescent bulbs, that cost the same as the GE bulbs, last longer than the GE brand. A sample of 50 Sylvania bulbs produces a sample mean of 940 significance level to support Sylvania's claim?

Statistics 2 (incomplete) 
PsyDAG,
An estimate of variability (e.g., standard deviation) is needed.

Probability and Statistics 2 
Kim,
The University of Southern Mississippi currently uses GE brad fluorescent light bulbs that have a mean life of 900 hours. Sylvania clams that its new fluorescent bulbs, that cost the same as the GE bulbs, last longer than the GE brand. A sample of 50 Sylvania bulbs produces a sample mean of 940 hours and a sample standard deviation of 70 hours. Is there enough evidence at the alpha = 0.05 significance level to support Sylvania's claim?